Tom Salinsky

Let me start by telling you three stories. The first is one you very likely know. A fraudulent tailor with no money to buy cloth nevertheless persuades a wealthy emperor that he will make him the finest suit of clothes imaginable. The emperor, deceived by the flattery of the tailor, believes that he is wearing a beautiful new outfit (made of very lightweight material). In fact, he goes out to greet his subjects stark naked. The rest of the crowd falls prey to the same mass delusion until a little boy points out the truth and then the spell is broken and the emperor becomes a laughing stock.

Now let’s also consider the story of the fraudulent Hitler diaries. Unlike the fable of the emperor’s new clothes, this is a true story (although I don’t swear that every detail here has been forensically researched). A fairly incompetent forger named Konrad Kujau wrote them himself during the early 1980s, staining the pages with tea to make them look old, before he sold them to the German news magazine Stern for several million pounds. Stern relied on the analysis of English historian Hugh Trevor-Roper who pronounced them genuine. Only after the fraud was uncovered did Trevor-Roper reflect on his thought process which included factoring in that Stern was paying a vast sum for the publication rights. Since fraudulent Hitler diaries had no value, he reasoned, these must therefore be authentic.

Finally, let us consider Edmund Landau and Fermat’s Last Theorem. As many people know, the brilliant 17th century mathematician Pierre de Fermat once scribbled in the margin of a book the equation xⁿ + yⁿ = zⁿ and asserted that he had discovered a truly marvellous proof that there were no whole number solutions where n > 2. (If n = 2, this is Pythogoras’s theorem.) He did not alas provide the proof, claiming that the margin was too small to contain it. The theorem was finally proved in 1995 by English mathematician Andrew Wiles, whose proof ran to many dozens of pages and build on the work of Gerhard Frey and Ken Ribet and required a deep understanding of semistable elliptical curves. Evidently, this was not the proof which Fermat had (or thought he had).

Fermat’s Last Theorem was for three hundred years the outstanding unsolved problem in mathematics. Not because it was particularly important (although Wiles’ work did open up new avenues of exploration) but because it had remained unsolved for so long and yet it could be stated in terms which anyone with a passing knowledge of algebra could understand. This meant that it attracted the attentions of a great number of enthusiastic amateurs, all of whom imagined that they would be the ones to solve the unsolvable.

The problem was compounded in 1908 when industrialist Paul Wolfskehl offered a large cash prize for a valid proof. Edmund Landau was the mathematician who was, for a while, responsible for assessing entries. Overwhelmed by the sheer number of submissions, many of which were little more than gibberish, he eventually had a stack of cards printed which read: “Dear [BLANK]. Thank you for your manuscript on the proof of Fermat’s Last Theorem. The first mistake is on line [BLANK]. This invalidates the proof.” He gave the job of filling in the blanks and returning the cards to his students.

What does all of this tell us about vaccines, conspiracy theories and the nature of evidence?

I had high hopes that the natural experiment currently being run in which tens of millions of healthy adults are being given a vaccine to help prevent them from contracting COVID-19 would silence the anti-vax brigade. If it were true that vaccines were toxic in any way at all, then we would see a huge wave of whateveritis sweeping the globe. No such wave has in fact materialised. The best (ugh) the anti-vaxxers could muster were a few cases of blood-clotting, which were at such a low incidence it was barely possible to connect them to the vaccine at all.

Although something of a side issue here, the case of blood clotting is instructive when it comes to vaccines in particular. Even though the incidence was so low that it was almost impossible to distinguish from the base level (some people will get blood clots anyway), it was determined that one brand of vaccine could increase the likelihood of developing a blood clot in some people. Okay then. We have identified a risk. Somebody fearful about developing a blood clot would be sensible to refuse the vaccine. Even if the risk is small – blood clots are nasty and can be fatal.

Except… that by not getting the vaccine, you are increasing your risk of contracting COVID-19. And one of the possible complications of COVID-19 is – blood clots. In fact, you are many, many times more likely to develop a blood clot as the result of contracting COVID-19 than you are from getting the vaccine.

Life is a game of risk vs benefit. The problem is that we tend to see risks where we take positive action (getting a shot) and ignore them where we are passive.

But that alone can’t explain the demented anti-vax brigade rapidly pouring on to social media to tell me that vaccines are toxic, that they aren’t properly tested, that diseases don’t exist and that I should do my own research. There’s an enormous appeal for some people in the conspiracy theory. It enables the conspiracy theorist to be the brave little boy in the story of the emperor’s new clothes, whose plain common sense and straightforward approach cuts through all of the sophisticated bullshit to expose the obvious truth. Of all the characters in that story, the one we want to be is the little boy. We don’t want to be the villainous tailor whose nefarious plans are ruined and we certainly don’t want to be the foolish emperor, taken in by such a simple trick. The appeal is obvious.

The trouble is that fate is manifestly unlikely to present us with such a situation. Randall Munroe in one of his XKCD comics, imagines a riposte to a parent who asks “If all your friends decided to jump off a bridge – would you?” as follows: “Which scenario is more likely: every single person I know, many of them level-headed and afraid of heights, abruptly went crazy at exactly the same time… or the bridge is on fire?”

Thus, Edmund Landau’s pre-printed cards. Landau didn’t need to read these crazy would-be proofs, and nor did he fear missing the mathematical discovery of the century. Anyone who had done the necessary work to even begin to attack this prodigiously difficult problem would of necessity be someone in the mathematical community who was publishing on a regular basis, and that is where the proof would turn up (if it were ever found). Landau didn’t live to see Wiles’ proof which was published nearly a century after his death, but its form and the manner of its revelation would not have surprised him.

That brings us to the key question. How can I, with a 2:2 in mathematics, know that Wiles’ proof is correct? I have read an outline of the proof intended for the curious lay reader, and I failed to keep the concepts clearly in my head. I do not have a mental model I can use for considering modular groups or elliptic curves or how they relate to each other. In fact, when Wiles’ proof was first published, an error was found and it took Wiles and a colleague several further months of work to patch the problem. Probably there are less than 100 people living who can read and appreciate every line of the final version – such is the obscurity of modern mathematics, all of it resting on pre-existing understanding of already fairly abstruse and difficult material.

In practice, I cannot “do my own research”. It is too late for me now to begin a decades-long career in number theory and I do not believe that the investment of time and energy would have a satisfactory payoff. So, how can I be sure that I am not poor foolish Hugh Trevor-Roper, who takes the fact that Stern believes in the Hitler Diaries as a reason to vouchsafe to that same organ that they are worth the sum proposed for their publication rights?

This is the charge that the conspiracy theorists level at those of us who subscribe to scientific scepticism. Some of the more obviously loopy ones will happily (and loudly) present themselves as the little boy pointing at the naked emperor. The idea that a minority opinion is likely a false one has never entered their head. They so enjoy the heady rush of being in the select group of the clear-thinkers and the far-seers that they never stop to question why no-one else can think those same clear thoughts and see those same far-off things.

But the charge of blind obedience or fatuous credulity is a harder one to dismiss. You’re just believing what you’re bring told. You’re Hugh Trevor-Roper falling for the Hitler diaries because some authority figure tells you they’re genuine. And look! They proclaim. Here is a paper which proves what I am saying is correct. Here is a doctor who doesn’t believe in germs. Here is an engineer who doesn’t believe the Twin Towers could have fallen without demolition charges. Here is an Air Force pilot who has seen flying saucers. Here is an astronaut who believes the Earth is flat. Here is a photo of Bigfoot. Here is a NASA scientist who can read minds. Et cetera and so forth.

Particularly with medicine, online debate-via-link-to-scholarly-journal is rife. Don’t take my word for it, look at the conclusion reached by this research team. This exchange of technical papers which neither party can properly understand is the height of pointlessness. I was (unwisely) drawn into a debate about the events of 9/11 on Facebook not long ago. A “new” paper had been published (several years ago), paid for by a group whose only purpose is to find any contradiction at all in the “official story”. This piece of mathematical modelling purported to show that the collapse of Building 7 was inexplicable without some additional force acting (they coyly stop short of saying the word “explosives”). Online it was easy to find people with far more expertise than me taking this paper apart, but the technical details were beyond me and so I saw no reason to comment on its contents.

What I found fascinating was the existence of another paper which had been published many years earlier which had modelled the collapse and found that the weakening of the structure due to the immense heat of the fires which burned for nearly an hour was entirely sufficient to explain what was observed on that horrific day. I was angrily told by defenders of the later paper that they had been researching the subject for years and were expert in this field (and by those same defenders that the online criticism which I provided links to was too technical). But the existence of this earlier paper seemed not to have registered.

Surely, if a second analysis has been performed which comes up with a different result, then the first question to ask would be: what was the difference in approach and what were the faulty assumptions made by the first team? Otherwise, what sense does it make to accept the conclusions of the second paper wholesale and completely dismiss all of the conclusions of the first? Without an understanding of what led to the difference, we’re simply being asked which black box we prefer. How can we possibly learn any objective truths about the world by doing this?

So, are we doomed to just saying “nobody knows” or committing to decades of re-education to get to the truth? I don’t believe so. In practice, we don’t need to even ask these basic questions. We don’t need to take the paper(s) apart. We don’t need to begin a lengthy career of detailed study to be able to critique the work of both teams. We can just ask instead: who else believes this?

Science proceeds in general not because of individual mavericks whose ideas seem crazy at first. Instead, evidence gradually piles up in favour of one conclusion more than the others. It was well-known and agreed by almost all medical practitioners that stomach ulcers were caused by stress, until it was shown that they were caused by bacterial infection. Now, virtually every doctor prescribes antibiotics. Palaeontologists used to believe that dinosaurs were likely scaly and reptilian. Now the preponderance of evidence suggests instead that many of them were feathered. The evidence moved the consensus of opinion over time.

With COVID-19, we have seen this play out as we’ve watched. Early guidance emphasised handwashing, because (for a variety of reasons) the importance of aerosolised viral particles was underappreciated. Now, both mask-wearing and crucially ventilation for indoor events is understood to be key. We didn’t know that when the pandemic started. But the consensus of medical opinion moved as the evidence accumulated.

And this brings me to my last bugbear regarding Internet vaccine warriors. We have seen that “do your own research” is ridiculous. We are simply not equipped to do anything of the sort. Instead, we need to appreciate that we are not likely to be the little boy pointing out that the emperor has no clothes – if everyone else sees clothes and we don’t, it’s far more likely that we are having a stroke. But the world is full of plausible sounding people who write articles and share videos (and post blogs!) and it’s easy to get seduced by their rhetoric.

“Watch this video, then you’ll understand.” “This doctor gets it, read what she writes.” “This book really changed my mind about this topic.”

So now we have an expert who is explaining complicated ideas in ways that we lay people can understand. We don’t have to worry about whether we can master the technical details. If this expert can explain this in a way which makes sense to us – then we will understand it. Right?

Wrong.

This is in fact the very error made by Hugh Trevor-Roper, who took the opinion of Stern as the basis for his conclusion. You can’t learn about scientific consensus by listening to one expert, no matter how slick, folksy, friendly or straightforward they seem.

Watching well-produced explainer videos on YouTube is a great way to learn about stuff and there are some great creators out there. But you don’t discover objective truths about the world by opinion shopping. You can’t sift through a few different takes on a complex subject and then decide “I’ve found my guy.” That only works if your guy is just saying what everyone else is saying. But if your guy is an outlier, you need to ask why. If your guy’s evidence – which might be highly convincing to you, a non-expert – has failed to convince the other experts, you need to ask why not.

So, if 99 doctors tell you that the vaccine is safe and it’s in your best interests and society’s best interests for you to take it as soon as you are offered it, the fact that you can find a 100th doctor who tells you something else is not relevant. At all. Because if that one doctor had real evidence that the other 99 were wrong, the other 99 would change their minds. How do we know? We have seen it happen in real time as the pandemic has played out, and we have seen it happen throughout the history of science. Your one paper “proving” that masks don’t slow the spread of this, or any disease, does no such thing. It’s an outlier. The consensus is that they do help. Your one paper is wrong. (Or it isn’t widely applicable. Or you’ve misunderstood it. Or it doesn’t say what you claim it does.)

Salinsky’s Second Law: You can prove anything with one study.

This has become a very long post, for which apologies. My point really is a simple one.

We believe our dentist when we are told we need a filling. We believe the mechanic when we are told that our car needs a new fan belt even though we couldn’t pick a fan belt out of a line-up. We trust experts all of the time and don’t feel the need to “do our own research” – unless and until a campaign grows around a particular topic and a small but insistent band desperately needs to believe that the emperor has no clothes on.

So, I don’t really mind where you fall on the scale from “I’m not anti-vax, I just don’t feel this has been tested enough,” to “You’ve been lied to! Disease isn’t real!” Both those positions are wrong because both of them misunderstand what science is and how it works. You can’t possibly know what “tested enough” means. You don’t (and I don’t) have even a basic working knowledge of how vaccines are routinely developed or tested and what happened in this case. The first error is in word eight. This invalidates the argument.

So, by all means “do your own research”. Research is fun. You can teach yourself a lot and you can end the day understanding more about virology, immunology, biomedical research and the spread of infectious diseases than you did at the beginning. But if you fail to take into account where the conclusion you are satisfied with sits in relation to the scientific consensus, you are not avoiding the error made by Hugh Trevor-Roper, you are committing it.

Don’t be Hugh Trevor-Roper. The bridge may very well be on fire.

Conspiracy theories regarding 9-11 never fail to get my sceptical antennae twitching, and I was particularly appalled at a recent spate of Facebook posts claiming that the supposed victims on board the doomed planes were actually alive and well and living in secret on a government pension. Fair enough for the armchair engineer to claim that the Twin Towers fell this way or that, but what on earth are the families of the dead passengers supposed to feel when they read this kind of nonsense? The clodhopping insensitivity of it is far worse than the stupidity and implausibility of the claims being made.

The claim that the planes were actually missiles (or holograms!?) is fairly clearly absurd on its face, contradicted as it is by such a vast array of video evidence. However, a more common and seemingly more reasonable claim is that the planes did hit the towers, but their eventual collapse was the result of a controlled demolition. On his Neurologica blog, senior sceptic Steve Novella invited one Michael Fullerton to debate the issue. You can read the back-and-forth here but it seems to me that Michael’s whole argument boils down to “I know the Twin Towers fell as a result of a controlled demolition because it kinda-sorta looks like that.” And in both his posts, Steve Novella did an excellent job at seeing past the hand-waving and name-calling and long-word-using to show the emptiness of this claim, while walking us through the basic physics of the situation with admirable clarity,

I posted a comment on the blog explaining that that you don’t even have to bother looking at the physics of the situation to know that the assertion that the Twin Towers fell due to a controlled demolition is absurd, if not actually insane. Anyone who wants to show that this is the case has some very, very hard questions to answer before they even begin to look at the physics involved. Here’s the rest of that comment in full…

Controlled demolition requires explosives – in the case of a building the size of the Twin Towers, massive quantities of explosives, in all likelihood hundreds of pounds. We are not talking about one guy smuggling a briefcase past security, we are talking multiple individuals making multiple undetected trips into and out of the World Trade Center carrying not just explosives but detonators, wiring and other paraphernalia. There is simply no plausible way in which that quantity of explosives could have been smuggled covertly into the buildings, and no evidence that they in fact were. Among the variety of conspirators, deceased and living, on American soil and overseas, none has been identified as playing this role. Nor was any evidence of explosives found in the wreckage. And in all the documents we have regarding the planning of the 9-11 attacks, there is no mention of explosives. Hard question one: exactly how and by whom and when were the explosives introduced?

Some might argue that given the planes and the burning jet fuel had already weakened the structure, less explosives would be required than if the planes had not struck, but this is a slippery slope to giving up the whole game. Once the stalwart Conspiracy Theorist has admitted that collision from a jet plane followed by raging fires burning for many minutes might weaken a building’s integrity, we have to start doing Hard Sums to figure out just how much it might be weakened, and as Steve has shown, the Hard Sums are not in the Conspiracy Theorist’s favour. But, as I say, we don’t need Hard Sums to dismiss this argument.

Even given that explosives could somehow have been introduced into the buildings – hard question two: why the need for a controlled demolition? You are already crashing fully-laden jet airliners into the buildings, which is bound to cause a tremendous amount of damage and loss of life. Why should it be an essential part of the plan to cause those towers to definitely collapse utterly? Remember, that until the planes are minutes away from the World Trade Center, no-one in power will have the slightest clue what the target is. As a terrorist attack it is chillingly perfect, unstoppable. As opposed to spending weeks carefully smuggling explosives into the building, which as soon as they are found, the entire game is up. Why risk the whole operation in that way?

But given that it is a fundamental part of the attack, for reasons unknown, to have the buildings not merely damaged beyond all likely repair but actually razed to the ground, why was the same approach not taken with the other two targets – the Pentagon, which suffered damage only at the impact site, and the Capitol building which was thought to be the target of the fourth plane? Neither of these exploded an hour or two later. Hard question three: why take one approach with one major American landmark and not take the same approach with either of the others?

But, okay, let us grant that for these particularly demented terrorists, and/or their Shadowy Government Overlords, it is tremendously important that the Twin Towers be razed to the ground, and entirely unimportant that the Pentagon and the Capitol building be destroyed completely – it is sufficient to merely damage those. And let us grant once again that our terrorists have the means as well as the desire to covertly introduce, install and detonate at will the prodigious quantity of explosives needed to topple two of the largest buildings on earth in a controlled demolition.

Hard question four: why bother with the planes? As noted, laboriously introducing package after package of explosives risks discovery far more, but if you already have the power to carry out such an operation, likely over several weeks, you now have the power to suddenly and terrifyingly wipe two buildings off the face of the earth. Why do you now bother attempting to hijack a couple of planes? At the very least, why not send them off to two further targets?

Okay, okay, okay. Let us grant – and I’m not sure who still would at this point, but here we go anyway – that our terrorists absolutely must raze the Twin Towers to the ground (but not any other targets); this is such an important part of the plan that they have risked everything to ensure it will happen, and they also have the means to covertly introduce hundreds of pounds of explosive, accurately position it, and detonate it at will; and that it seems sensible to take effectively a belt-and-braces approach by first crashing a plane in to each building, and then setting off their explosives an hour or so later.

Hard question five: why the delay? The purpose of a terrorist attack is to spread terror, to kill innocents and to make the government seem powerless. In the time which elapsed between the planes hitting and the buildings falling, many, many people were evacuated from the buildings and taken to safety. If the explosives had detonated immediately the planes had hit, the result would have been no less spectacular and far more fatal.

Ah, but that might reveal the presence of the explosives. While those who obediently swallow the Official Story might be fooled by the towers collapsing after the fires had raged for an hour, they surely will detect the presence of explosives if the towers fall as soon as the planes hit?

Which brings us to the hardest hard question. Hard question six: why continue to keep the explosives secret? Why on earth would Al Quaeda not be boasting about the bombs? How can it possibly ever, ever, ever advance their cause in any way at all to have secret bombs inside the World Trade Center? Even if the terrorists are acting in cahoots with the government (or secret world government or whomever) pinning the bombs on the terrorists makes their terror even more terrible, whereas keeping the bombs secret achieves nothing whatsoever.

I know that the Twin Towers did not fall due to a controlled explosion because the very idea makes no sense on any level. Adding secret bombs complicates the plan, makes it far more likely to be uncovered, is not necessary, requires a mysterious unmotivated pause in the day’s action and would have been acknowledged by the terrorists, or pinned on them by the government.

That the physics and the video evidence also supports this is welcome, but unnecessary.

Overt planes but secret bombs. For fuck’s sake.

For various reasons, I was recently put in mind of an exchange of Facebook comments which spun-off the interaction I had on Quora with one Zoletta Cherrystone (which you can see archived here). I copy-and-pasted the Facebook interaction at the time with the intent of putting it up here, but I never got around to it. Here then is a lightly edited account, with some of the conversational cul-de-sacs removed and some of the spelling and grammar tidied up. As I haven’t asked the other party for their permission, I have protected their identity behind an obvious pseudonym. There are also some references at the bottom should anyone be interested in further reading.

Here we go…

References

California (missile) contrail

• News coverage
• Explanation

Rendlesham Forest

• General site containing a variety of information
• Wikipedia entry giving a detailed account
• Site including the entirety of the Halt tape and documents released under FOI
• Skeptical site which analyses the main claims
• Ian Ridpath’s site which includes the airmen’s statements made at the time

Happy Christmas everyone!

I’ve been playing around with Quora recently, which is a new social website revolving around questions and answers. Since some of the questions posed are contentious, it’s possible to get into some quite fun debates on there, although the system of voting and thanking generally means that sane, well-reasoned and well-evidenced answers rise to the top.

In a recent exchange, I ended up posting a very long comment which the Quora software mangled somewhat when I pasted it from Word. I’ve therefore reproduced it here, with a few snippets of the earlier conversation for context. You can see the whole saga, complete with any future additions, here.

Zoletta Cherrystone
I have had more than one ‘ghost’ experience, and completely believe in the spiritual world. I believe this without doubt, because of what I’ve witnessed with my own eyes.

Tom Salinsky
I’ve seen plenty of things with my own eyes which were later proved not to be the case. You’ve never seen an optical illusion before? First-hand testimony is a very poor way to establish objective truths about the world.

Well, Tom, I don’t think there’s a test to prove that pretty much all of us can ‘feel’ when a person is standing behind us, but we all know we can.

I said, earlier, that I’ve had more than one ‘ghost’ experience. It was a huge understatement. I’ve had dozens, from early childhood until the present. Things that simply have no other explanation, and some of which are too connected with a dead relative to dismiss.

An optical illusion is not going to explain away a light switch snapping (I say snapping because this was a very old one, and hard to maneuver) into the off position. Or a book physically being placed in a peculiar way in a room other then where you left it just as you fell asleep with no one else in the house with you. Or hearing your name being spoken aloud in a new house when you’re in it entirely alone, accompanied by other instances of objects being slammed down at key moments (no vibrations, no way for these items to casually fall on their own) and then to make phone calls and find out that the previous owner experienced all the same.

“Am I a man dreaming I’m a butterfly, or am I a butterfly dreaming I’m a man?”

With all the paranormal investigators out there recording voices, snapping photos, and catching things on tape, that’s about as much ‘proof’ that anybody is ever going to get, yet still it is dismissed.

So my question to you now becomes this: What is required to ‘prove’ this phenomena?

This is going to be far too long, but here goes…

ZC: Well, Tom, I don’t think there’s a test to prove that pretty much all of us can ‘feel’ when a person is standing behind us, but we all know we can.

TS: This shows a distinct lack of imagination. Can you really not conceive of a way to test this hypothesis? Here’s one. Blindfold a series of subjects and deafen them by playing white noise in their ears (since this is not a test of one’s ability to see or hear people). According to a predetermined, but random sequence, have people either stand behind them or not, and have the subject indicate when they feel a presence. If they are right much more often than chance would suggest then there is a real ability here. BUT UNTIL A TEST LIKE THIS IS DONE, we can’t say for sure that such a phenomenon exists. Personal testimony is not enough. Confirmation bias will ensure that we remember only those occasions when we ‘feel’ someone behind us and are correct. (I do not give an opinion as to whether this ability is real or not.)

ZC: An optical illusion is not going to explain away a light switch snapping (I say snapping because this was a very old one, and hard to maneuver) into the off position… etc

TS: All of these are artifacts – events in the past for which the only evidence is your testimony, which may or may not be distorted by time, the limitations of your senses and your desire to believe in the existence of spirits. But you don’t get to jump from “I have no explanation for the movement of this light switch / book / strange noise / falling objects, and BECAUSE I HAVE NO EXPLANATION IT THEREFORE MUST BE A GHOST.” You are just substituting one unknown for another. I submit that all of these phenomena, even if they could be definitely established as real (which at the present time, they cannot) could be equally well “explained” by aliens, Jesus, elves, fairies or any other fantasies you choose to invent. Finding out objective truths about the world is not done by identifying apparently anomalous events and then announcing that your predetermined idea is “the only explanation”.

ZC: With all the paranormal investigators out there recording voices, snapping photos, and catching things on tape, that’s about as much ‘proof’ that anybody is ever going to get, yet still it is dismissed.

TS: But not dismissed without reason. Dismissed because the supposed evidence is so weak. “Ghost” photos are routinely analysed and shown to have mundane explanations, but even when no mundane explanation presents itself, my argument above still applies. What you call “ghost”, I call “alien”, and someone else calls “Jesus” and so on, depending on taste, upbringing, bias and so on – depending in no way on the phenomenon itself.

Recording voices is a particularly clear example. So-called EVP (electronic voice phenomena) are generally agreed to be artifacts of recording devices with automatic gain control, coupled with the human brain’s automatic pattern-detecting habits. The former is a matter of electronics. If you have a device which records more when the environment is quiet, it will record more NOISE. Then, a person hoping to hear particular words or phrases will manage to pick them out of that noise. You rubbish my showing how your subjective experiences may be unreliable with reference to optical illusions, but this is an auditory illusion. The phenomenon is known as pareidolia – people finding patterns in randomness – and it explains why people believe they see Jesus in a piece of burnt toast, faces on the surface of the moon and hear voices in static.

Here’s a great example of how easy it is to hear words that aren’t really there – once you know what it is you are supposed to be hearing.

Skeptic and magician Derren Brown was confronted with a devotee of EVP who swore that when he asked questions of spirits, they obediently provided meaningful answers which were recorded during silences on his Dictaphone. When Derren went recording with him and was given the opportunity to ask a question himself, he said “If there really is a spirit there, confirm your presence by remaining silent once I’ve finished speaking.” On playing back the tape, the usual roar of static was heard – exactly as one would expect if the phenomenon was entirely due to automatic gain (and subsequent pareidolia). Exactly the opposite behaviour of the previously always-obliging phantoms.

ZC: So my question to you now becomes this: What is required to ‘prove’ this phenomena?

TS: Just the same as to prove any phenomena. At a minimum: the result must be repeatable (which your accounts of magic light switches and falling objects are not, unless you propose to take me to a haunted house – a proposition I would relish); and it must have a low probability of happening by chance (which is not true of EVP). I have yet to see a piece of evidence for ghosts which would even meet these two criteria, but notice that these are necessary but not sufficient to establish that a particular phenomenon or effect is real. And even if the reality of an effect is established, this doe not in turn immediately allow us to conclude that the cause is a departed spirit. Once again, you only get to jump straight from “unexplained” to “ghosts” by CHOOSING ghosts, not by making a genuine discovery about the world.

The magician and escapologist Harry Houdini devoted many of his later years to exposing the mechanisms used by fraudulent psychics, but nevertheless he hoped against hope that the stories they told were true and that he could be reunited with his beloved mother. Before he died, he arranged with his wife that she should hold a séance every Halloween after his death. He also gave her a secret phrase known only to the two of them. Houdini’s codeword reproduced by a psychic after his passing would have been marvellously strong evidence for the existence of life after death. Sadly, after ten attempts and no appearances by Houdini’s spirit, his wife abandoned the task.

Of course, the real reason that most people don’t believe in ghosts is not because the evidence is so flimsy (although it is). It’s because there is no plausible mechanism which could possibly exist to preserve the personality after death. Every single experiment ever done on the subject shows us that the personality and memories are generated by the brain. After death, that pattern of neurons is destroyed and no possible way exists for that pattern to be preserved, with no power being fed in to the system and with no physical substrate on which the pattern could be recorded.

But I don’t even ask for scientific plausibility. Let’s start with one repeatable, low-probability event, the experiment designed in such a way as to rule out conscious or unconscious fraud. If we discover a genuine phenomenon, then we can start theorising about possible causes.

See, I said this would be too long.

Clarke’s Third Law: Any sufficiently advanced technology is indistinguishable from magic.
– Arthur C Clarke

Harry Potter bursts back on to our screens again this week, with the final book split into two no-doubt lumberingly ponderous full-length motion picture “events”. But, we must take solace in the fact that a) it will soon all be over and b) remember that magic has been a huge part of the fabric of narrative since stories began and try not to be too grumpy about the success of this “franchise”. If the appeal of stories is their ability to take us to places and show us things which ordinary life denies us, then it’s easy to see why magic should play such a strong part in especially early stories. Most fairy stories have a magical element – in fact the word “fairy” implies magic.

As we grow up, we leave such things behind, for the most part. The broad appeal of those Harry Potter books and films (and the amusing existence of editions of Harry Potter novels with “adult” covers and a £2.00 price premium) is a notable exception, but especially among male readers, although fairy stories are left behind, fantasy and especially science fiction stories remain popular.

I have observed before that the key feature of stories, the primary quality which distinguishes story from not-a-story is cause and effect. Without cause-and-effect, all you have is a succession of images. (Ironically, if you present such a succession of images to an audience, they are apt to invent the missing cause-and-effect, justifying the action they see in terms of A causing B, such is the storytelling hard-wiring in the human brain.)

Even in stories which don’t present themselves as fantastical, we can often see cause-and-effect being applied in a very limited way. Consider the phenomenon, often noted in pulp, pop or escapist fare, of “goodat”. If characters suddenly announce some convenient talent, skill, expertise, relationship or ability hitherto unmentioned and unsuspected, the audience is likely to feel cheated. “Oh, didn’t I mention I can speak Japanese / crack safes / recite pi to 150 decimal places / fly unaided / control birds with the power of my mind?” It doesn’t matter if these powers are magical, merely require talent and/or practice or are borderline. Conversely, however, if it is set-up that the character in question is “goodat” languages / escapology / mathematics / psychokinesis / animal sympathy, then the audience will probably accept almost any manifestation of this ability, no matter how fantastic. The archetypal version of this would be – as I think Eddie Izzard noted – the ability of someone who is goodat computers to hack into any system in a matter of minutes, just by waggling their fingers lightly over the keyboard and announcing “I’m in”.

So far, so fair enough. Storytellers take short cuts but even bad ones stop short of outright cheating. But there’s a difference between someone, for example, using their total mastery of Spanish to eventually make communication possible with a person who speaks only Catalan – and on the other hand, somebody uploading a Macintosh virus to an alien computer. I suggest that the latter is magic and that the distinction lies in the cause and effect.

Let’s pause for a moment and consider three ways in which a fictional person may be made to disappear before our eyes – Star Trek transporters, Star Trek phasers and Harry Potter vanishings. In Star Trek as you may know, a device known as a transporter is able to whisk people from one location to another. In effect, this device disintegrates the body at one end, transmits only the pattern (transmitting data is much quicker and easier than moving mass I suppose) to the other end, where it is reassembled. The practical difficulties of achieving this are not to be underestimated. A human being is composed of around 10^25 atoms, the exact location and type and state of which all have to be recorded. That’s a heckuva big file. This data is then transmitted to a precise location where no specialised machinery exists, and then the original body is reconstructed out of – what exactly? The TV shows, films and books are generally vague on this point.

But you could (and I’ve no doubt others have) construct vaguely plausible theories about what is going on here. The transporter pad creates a sort of cone or column around the person to be “transported” and everything within that column is processed. 23rd century computers have to “lock on” to remote locations. Maybe something like a tractor beam (not that that exists yet either) is used to process atmospheric atoms within a similar column at the destination in order to make the mass required to reconstruct the transportee. It’s a hugely big problem, but as presented in Star Trek, a hugely big solution is required to make it all work – and sometimes it doesn’t. It can go wrong, with horrible consequences. So this is borderline, but I would say, provided one makes allowances for three hundred-odd years of technological advancement, there is cause-and-effect here, and crucially, the cause (although we can’t examine it all in detail) seems sufficient for the effect.

Now compare those instances with death-by-phaser. Here’s a YouTube video. Watch the phaser deaths that occur around the 1’05” mark.

A phaser beam hits someone and they simply disappear. On a very basic level, there’s cause-and-effect here. Pull trigger on phaser, phaser beam hits redshirt, redshirt disappears. But what do we suppose the phaser beam is doing? It’s not just a narrow pencil-thin column of heat, it doesn’t drill a neat hole through its unfortunate victim. It’s not affecting the air between the barrel and the target, so it’s not radiating out a destructive cone – that would also affect surrounding matter, or if you were too close, not get the whole target. No, the phaser, or the beam itself, just “knows” what is target and what isn’t, what is to disappear in a flash and what is to be left unaffected. Not only is there no plausible mechanism by which this information could be imparted, the presentation doesn’t even begin to hint at a possible solution. Transporters are almost certainly impossible, but at least the series waves its metaphorical hands in the direction of a proper cause. Here the given cause is far to slight for the actual effect.

So, to me, death-by-phaser is far more like a wand being waved and a word being spoken and a Harry Potter character vanishing into thin air. No mechanism exists to define the scope of this action. No care must be taken to isolate only that which you wish to vanish. The waving of a wand and the saying of a word are in no way sufficient to account for the immensity and the complexity of the action which results – which is why Harry Potter is magic and not science-fiction. But magic gets smuggled in under our noses all the time. “I’m in” is a form of magic, as is the bus jump in Speed as is Radar’s ability to anticipate Colonel Blake and so on. The rule is – if the cause is sufficient for the effect, then what you have is science, but if the cause is insufficient for the effect, then what you have is magic.

But this applies to the real world of knowledge, science and medicine as much as it does to storytelling. Remember that humans look for cause-and-effect even where none is present. So, in earlier times, we ascribed the sudden and unpredictable shaking of the earth to the wrath of peevish gods. But since we have no idea where these gods are, what we have done to annoy them, or how they physically interact with the earth to cause such violence, this is magical thinking. Modern plate tectonics provides a much more thorough model (although not yet quite complete) with all the cause-and-effect you could wish for.

Another area where this test can be applied – one familiar to regular readers – is that of homeopathy. Both homeopathic and pharmaceutical treatments for a given condition, joint pain say, have the same superficial cause-and-effect appeal. You take pill. Pill makes pain better. But ask the chemist how their pill works and the answer will include fantastic quantities of detail, each element enhancing the cause-and-effect in the account. Non-steroidal anti-inflammatories inhibit cyclooxygenases, leading to a decrease in prostaglandin production. Opioids bind to and activate opioid receptors in the body’s tissues, and so on and so on. As with plate tectonics, the account may not yet be complete, but gaps are acknowledged, and effort continues to plug them. Pharmacology is science.

With your homeopathic pill on the other hand, the explanation is far sketchier. Like cures like, you may be told. How? It just does. Dilution increase potency. How? It just does. Does that mean half a pill will be twice as powerful as a whole pill? No, you have to dilute and the succuss (shake). What does that do? We don’t know. A cursory examination of the cause-and-effect supposedly driving homeopathy is enough to tell anyone that a woefully insufficient cause exists for the claimed results. Thus, we can confidently state that homeopathy is magic.

And, of course, the other thing we know about magic is that it isn’t real.

As many readers will know, Stephen Fry got himself into trouble recently when an interview was published in which he is quoted as making various observations about the natures of male and female, gay and straight sexuality. The interview is not currently available online, but if you wish to read extracts from it, then try The Guardian’s coverage for less than total hysteria.

The outcry over this has driven Fry off Twitter (again) and everyone is now weighing in with their own opinion. As ever, this debate boils down to the following trite observation – men and women, taken as groups, differ in some respects but not in others. Thus, those looking for a fight can make lengthy lists of the differences and rubbish those who emphasise the similarities, or can play down the differences and give endless examples of similarities instead.

But I don’t believe Fry’s personal musings should be cause for alarm or criticism. They were offered in no way as the last word on the subject, despite his possibly rather conclusive tone, and notwithstanding his subsequent claims to have been misquoted. And they seem on their face to be perfectly fair enough. It is a readily observable fact that gay men find anonymous sexual encounters easy to come by with no need to for money to change hands. That, further, while the world is crawling with prostitutes and rent-boys, the number of straight male escorts is vanishingly small (although there’s no shortage of straight men who would volunteer to earn a living in this way). That Playgirl magazine, launched at the height of the women’s lib movement and marketed to straight women is in fact read largely by gay men. Why should not a gay man venture some speculations as to the nature and cause of these obvious differences? Especially one whose non-professional opinion is eagerly sought on a very wide range of other topics – literary, musical, technological, cultural, sartorial, zoological – almost no subject is out-of-bounds where Stephen Fry is concerned, except for female sexuality apparently.

But it doesn’t take the brain of Stephen Fry to detect the obvious difference between the sexes which emerges after even the most cursory examination of the evidence, and which no list of thoughtful similarities will do anything to dispel. Men and women certainly do tend to process the world of sex and sexuality differently. In this post, I will attempt to give an explanation of why this is so, drawn from several different pieces of research, documentaries, pop science books and lectures I have consumed over the years. Regrettably, I find myself unable to footnote any of this very extensively, but if anyone really wants to take me on, then let’s head to the comments and/or the library. Most of this is logic, observation and common sense anyway. Let’s start from first principles.

Preparatory notion 1. Men and women are different and similar and diverse

For much of the rest of this blog post, I am going to be talking about men and women as groups, types or Platonic Ideals. But it’s perhaps necessary to acknowledge that a human man and a human woman will no doubt have far more in common than a human (of either sex) and a chimp. Or indeed, a dolphin, a racoon, a banana or a bicycle. It’s not that these similarities between humans don’t exist, they simply aren’t my topic for today.

And both groups are also terribly diverse. It’s certainly possible to identify women whose behaviour sounds much more like the prototypical male I am describing, or vice-versa. I’m not suggesting that each group is entirely homogenous, and that any particular man or woman you happen to meet (or be) is guaranteed to perfectly exemplify whatever behaviour I am claiming for that group. I am claiming, however, that certain behaviours are much more typically found in men than women, or the other way round, and I don’t want the presence of outliers to distract us from the interesting conclusions we can draw about the great majority, somewhere in the middle of the bell-curve. Once again, it’s not that these outliers don’t exist or aren’t interesting – it’s just that they aren’t whom I wish to write about today.

Preparatory notion 2. The mind evolved

The field of evolutionary psychology is excitingly controversial, although those who oppose the very idea of it, often seem to be to be attacking a straw man (as in this debate between Stevens Pinker and Rose). No serious researcher is taking the field to the absurd excesses described by those who seek to denigrate this approach, and like any scientist, evolutionary psychologists are free to speculate, while being careful to separate such speculation from evidenced conclusions.

But the basic idea that the mind evolved can hardly be denied. Tiny kittens play-fight to discover how to defend themselves and catch prey, but this play-fighting is instinctive, not taught to them. Birds hatch with all the required muscle co-ordination for flight and don’t require the blank slate of their brains to be written on by an extensive programme of schooling. Human infants learn to talk even when exposed to primitive and incomplete versions of what will become their native language, as in the deaf children of hearing parents who effortlessly turn the clumsy signs of the adults closest to them into the full linguistic richness of British Sign Language (or whichever).

Although humans are blessed with an extra capacity for general reasoning and abstract thought, compared to other animals, nevertheless much of what we do remains instinctive, unconscious and shaped by billions of years of evolution, rather than a few thousand years of culture. Thus we crave foods rich in salt, fat and sugar because moderate quantities of these things are essential to our survival, and they were not always easy to come by in the African savannah. If we failed to prioritise acquiring them, or passed up opportunities to consume them, we tended to be outcompeted by those that did. These being instinctive actions, shaped and promoted (though not actually controlled moment-to-moment) by our genetic makeup, a proclivity for aggressive consumption of salt, fat and sugar became the norm in the population.

Today, when foods high in salt, fat and sugar are readily available (at least in some parts of the world), this adaptation is no longer such a benefit, but evolution shapes us only slowly. We’ve needed salt to survive for hundreds of millions of years, but McDonalds has been in business for only a few decades.

Humans evolved around a million years ago. Hominids around 15 million years ago. Primates around 75 million years ago. Mammals about 250 million years ago. Tetrapods around 400 million years ago. Vertebrates 500 million years ago.

Sex evolved about a billion years ago.

So we’ve been boy and girl for almost as long as we’ve been anything at all. It’s not inconceivable that evolution might have shaped male and female brains differently, given a billion years in which to work. But we’ll come back to men and women once we’ve considered another more general point. We are now ready to begin asking some serious questions about sex and sexuality.

Question 1. How do we choose our mates?

Evolution isn’t only about survival of the fittest (which itself doesn’t survival of the strongest, or healthiest – “fit” in this sense means suitable or most fitting to the environment). Not just natural selection, the weeding out of the least fit, but sexual selection plays an important part. The price for sex (no we’re not still talking about rent boys and hookers) is that by reproducing sexually, I only get to pass on half of my genes. So I need to be pretty careful that my super-duper genes aren’t being dragged down by your inferior ones. Thus we get careful choosing of mates, display behaviour and phenomena like peacock’s tails. A peacock doesn’t need an elaborate tail for its own survival – quite the reverse, they are cumbersome and cost energy to maintain. But a peacock who can sustain this preposterous plumage must be, in general, a superior specimen, blessed with a robust constitution, excellent health and fitness and bags of stamina, at least some of which may be genetic in origin. Thus a discerning peahen who prefers to mate with the larger-tailed gentleman will find more of her genes in the next generation, whereas those who seek out the tiny-tailed may discover that the next generation is bereft of her genetic bounty since her offspring suffered from the same lazy attitude, heart condition or inherited disease as their dad.

Note that none of this is mentally considered by the peahen. It is simply a fact that because peahens who prefer to mate with big-tailed males have a greater genetic influence on the next generation, so  necessarily, the next generation contains a higher percentage of peahens who get turned on by big tails.

Quite obviously, even as sophisticated adult humans, with all our language and culture and technology, we also have mate preferences that we didn’t decide for ourselves, but simply woke up with aged about 10. And while it (once again) isn’t true that there is a single monolithic standard of beauty or attractiveness, patterns do emerge and so Marilyn Monroe is generally feted for her beauty whereas Bella Emberg received such compliments less frequently.

But even if we ignore the problem of establishing a global standard for attractiveness, we can still accept that people tend to rate people they meet in terms of how attractive they are – and we need not limit ourselves to physical beauty. A potential mate may strike you as attractive because of their power, charm, vulnerability, sense of humour, kindness, personal wealth, liking for adventure, exotic accent or any one of a number of other reasons. But, if forced to, you could give any person of the appropriate sex whom you happened to meet a rating on an imagined desirability scale. So if you should want a global measure, you can think of this as the average across all potential mates.

Sexual selection tells us that in the game of mating, those whose combined desirability scores are the highest are going to be those who most influence the next generation’s gene pool, and so evolutionary theory tells us that behaviour which tends to lead to this outcome will be selected-for and so come to dominate. That leads us to…

Thought experiment 1. The ice rink

You are one of twenty players (sexes are not relevant for the purposes of this game) who will shortly be let loose on an ice rink. It doesn’t have to be an ice rink, but freedom of movement is key. Each of you wears a number on your back, allowing you to be ranked in order from 1 to 20. Numbers have been assigned randomly and secretly, so – although you can see clearly what number somebody else wearing, you cannot see and do not know your own designation.

The game is to find someone who will agree to leave the ice-rink with you, holding your hand, and the aim is for each pair to attempt to maximise their combined score. So a 9 who leaves the rink holding hands with a 5 will score 14, but will be beaten by an 8 who leaves the rink holding hands with a 11. You can change your mind as often as you wish and the time limit is fairly generous so no-one is making any snap decisions.

The game begins. What is your strategy? The obvious (and correct) strategy is to immediately start looking for number 20. Regardless of what number is on your own back, nothing will give you a higher score than leaving with number 20 in tow. Pretty soon number 20 is spotted and quickly has a great many potential partners. There’s a 1:20 chance in fact that this will be you. So let’s assume it is – you are busily looking out for number 20 when you gradually realise that everyone else has come looking for you. You are number 20! Who are you now looking for? Well, the best score you can possibly get will now be 39, provided you can find number 19. So number 19 now becomes the only person whose hand you are willing to hold. 19 eagerly agrees to hold your hand, and you both happily leave the ice rink having won the game. But the game isn’t over yet.

Once 19 and 20 are paired off, all attention naturally switches to number 18, who is now the best prize available. Number 18 will now only accept the advances of number 17, and so on. By starting with the rule “maximise your combined score” we end up with everybody pairing up with the closest number to them.

Answer to question 1. People choose as their mate the most attractive person who will accept them.

Again, “attractive” is assumed to have a multiplicity of meanings, but this complexity doesn’t change the fact that we find some people more “attractive” than others – even if we couldn’t give a very satisfactory definition of “attractive” even when asked. And because we both seek and select, we reject people if we think we can do better, but set our sights as high as we dare. In life, unlike in the ice rink game, we get a sense of our own level of attractiveness (even if, or especially if, this changes over our lifetime) and so don’t bother approaching those way out of our league because the risk of rejection is suicidally great. When we encounter pairs who appear to buck this trend, they tend to be figures who attract startled comment. “What does she see in him?” and so on. This is precisely because they are outliers and not the norm.

Preparatory notion 3. Game theory can help us understand human psychology

Evolution finds solutions that “work”, where “work” in this sense can be taken to mean “increases the representation of those genes in the gene pool of the next generation”. Evolution in this sense is circular. Natural selection means survival of the fittest. What does “fittest” mean? Those who tend to survive. But if a subtly different shape of fin, a different trade-off in heart construction, or a thicker, shaggier coat creates a survival advantage, then over generations, a population of organisms will shift in that direction. Evolution tests countless tiny variations on the currently best designs and – especially if the environment changes – discards the ones which don’t help and retains the ones that do. It isn’t guaranteed to find perfectly optimal solutions, and if the environment changes very rapidly then evolution may not be swift enough, but when it works, this is how it works.

In just the same way, when it comes to sexual selection, evolution can generate variations on brain construction which give rise to different psychologies which give rise to different strategies. Those strategies which tend to maximise inclusive fitness – in other words those which don’t only aid survival for this individual organism but which contribute to their ability to genetically dominate future generations – will be selected for. But note that even homo sapiens is not granted a psychological makeup which is explicitly and consciously focused on inclusive fitness maximising. If it were the case that, for example, men were consciously focused on maximising their genetic representation in the next generation, that most men would be ferociously keen to donate to as many sperm banks as possible as often as possible – but this is not a solution which evolution could plausibly find. We would expect men to enjoy orgasm however, and this they generally do.

Of course, sex and reproduction is only worthwhile if you live long enough and so other forces come in to play. Some male mammals (although no females as far as I know) will eat their own young if food is scarce. The calculation (not performed consciously of course) is that if I eat my kids today, I can father lots more offspring when there’s enough food to go around. But if I don’t, I’ll die now leaving only this litter, who will probably die themselves. Layered on top of all of these evolved, primal, psychological forces are more recent, subtler drivers such as the need for acceptance, social status and so on, not to mention a whole other wealth of cultural, societal and fashionable forces which also act upon us, and all of that is without even mentioning all of the personal preferences which make us unique.

But game theory – the mathematical study of what tactics are most likely to lead to success given certain rules to play by – can certainly be employed to allow us to discover how evolution might have shaped this part of our mind. We can then look at human societies and behavioural norms and come to some conclusions about how many of these primal needs are preserved, and how many are muffled or eradicated altogether.

And here we must – for the first time – start considering men and women differently, instead of considering evolution, psychology, mate-selection and sex-differences simply as phenomena.

Question 2. What is a man’s best mate-selection strategy for maximising inclusive fitness?

Since the mind evolved, and since the mind evolved under this kind of selection pressure, we can be fairly sure that most men will be seeking a mate who is the most attractive person who will accept him. But maximising inclusive fitness doesn’t only mean finding a life partner. The potential cost of sex to a man is very little. He will never have to bear the child through pregnancy and the time which elapses between conception and birth may very well mean that he is no longer conveniently at hand to raise the child, or possibly no longer identifiable as the genetic father. But like a gambler with an unlimited bankroll, there is no reason for him not to keep rolling the dice again and again and again. Given the choice between having sex with number 18 and having sex with number 11, regardless of what number is on his own back, he would prefer number 18. But he’ll cheerfully have sex with number 11 if no-one else is around.

For men, promiscuity makes sense. Why would you not have sex whenever possible, provided you are still eating enough and providing a decent enough shelter to ensure that you will still be fit and healthy enough to have more sex tomorrow? There is no cost and from an evolutionary point of view, it’s an easy (and fun!) way to out-compete less eager rivals.

Not only that, but it’s also easy to see why men would prefer to have lots of sex with lots of different partners, rather than settling down with just one straight away and raising a family. All that time spent looking after your first child is time you could be spending anonymously fathering dozens more.

Question 3. What is a woman’s best mate-selection strategy for maximising inclusive fitness?

For women, however, the picture is vastly different. There is a tremendous potential cost for a woman in having sex with a man. This cost is twofold. Firstly, if she becomes pregnant, she will have six-nine months of discomfort, followed by many years of expending energy in childcare (this is a potential cost for a man too, as mentioned, but an all-but guaranteed cost for a woman).  The second cost is more subtle. Gestating this baby is a missed opportunity to gestate the baby of another man. Thus, because she wants her genes to be given the best possible advantage in the next generation, she will strongly prefer to have babies only with the most attractive men available.

Now, this is all very well if you are number 20. You simply wait for number 19 to come along, refuse to have sex with him until you have some way of forcing him to stick around and share the burden of childcare with you and give birth to a series of prodigious wonder-children.

But what about the rest of the population? You might imagine that the ice-rink experiment teaches us that number 12s just have to settle for living with and raising children with number 11 or number 13, but a better strategy exists for the female of the species. The possible lack of certainty about paternity here works in the woman’s favour. The very best strategy for all but the most desirable female is to find the most attractive male who will accept her, and then get him to help bring up the child which she gives birth to after having had sex with a much more attractive man.

Question 4. What evidence do we see of this in the modern human world?

This trio of observations – men and women each seek the most attractive person who will accept them, men favour promiscuity over a stable relationship, women need both a helpmate and a genetic mate but they don’t have to be one-and-the-same – unlocks a tremendous amount of human sexual activity, even though almost nobody actually gives totally free reign to these desires. From these observations we should expect to see – and do see…

• Men are more likely to have multiple sexual partners, and will resist being “tied down” when still young and studly.
• Women will be much more choosy about with whom they have sex and will be looking for life partners from a much younger age
• Men will be very concerned about paternity and feel extremely threatened if it is suggested that the baby they are cradling might have been fathered by another man, unbeknownst to them.
• Both sexes will be concerned about the possible consequences of infidelity on the part of their partner, but each will be concerned about different outcomes. Men fear cuckoldry. Women fear abandonment. As Steven Pinker puts it, women who discover that their man is cheating think “he’s having sex with her – oh god, what if he’s in love with her!?” whereas men who discover that their woman is cheating think “she’s in love with him – oh god, what if she’s having sex with him!?”
• Men, who are briefly deciding where to deposit their sperm before moving on to the next conquest, will tend to make the decision about on whom to bestow their genetic gift on the basis of factors which can be assessed quickly – chiefly physical appearance. Women, who are deciding at their leisure with whom to attempt to form a pairbond, will tend to weigh up a wider variety of factors before they commit to a sexual liason, including (but not limited to) trustworthiness, resourcefulness, kindess and so on as well as physical beauty.
• And – as Stephen Fry noted – we should expect to see, and do see that gay men, genetically predisposed towards promiscuity but not having to play the mating game with women, will tend to be very promiscuous (despite the fact that no offspring will ever result from this behaviour).

Objecting that these behaviours are cultural rather than genetic misses the point three times. Firstly, it is surely not a coincidence that the biases we would expect to see thanks to evolution exactly coincide with our current cultural biases. Secondly, it entirely skips over the question of where these cultural biases come from.

Maybe because of these two (and I’ll come to the third in a moment) some who took offense at what Fry had to say simply deny that the behaviours listed above are remotely commonplace. Now, I’m not offering any particular evidence that they are, but they resonate profoundly with how men and women are depicted, talked about and represented. Offering a handful of outliers – as discussed earlier – does nothing to provide evidence that these very, very familiar behaviours are, on the contrary, vanishingly rare. It only offers evidence that they are not the totality of human behaviour. Fine. Nobody ever said they were.

And nobody ever said they were desirable either, which is the third way in which taking offense at Stephen Fry’s remarks misses the point. Simply because these behaviours are commonplace doesn’t mean that we should be happy with them, blithely accept them and even if we don’t like them, shrug our shoulders and say “there’s nothing we can do – it’s genetic.” Genetic tendencies are not implacable predestinations. They are powerful forces, but other forces certainly exist, and as thinking creatures with the capacity for abstract thought, rationality and selflessness, we can ask ourselves what kind of society we would like to live in and do what we can to bring that about.

And so, in many Western societies, attitudes – especially straight male attitudes towards women – are profoundly shifting away from what might be expected given these primal, evolutionary forces; but the shift is not, and I doubt ever will be, so complete as to eradicate any meaningful difference between the sexes. If you doubt that these evolutionary forces still act on our unconscious desires and behaviours, then consider this elegant study (sorry, no citation).

Researchers interviewed, took photographs of and took blood tests from a number of young women in nightclubs. From the interviews, they determined whether the women were single or in a stable relationship. From the photographs, they measured how much bare skin they were exposing as a percentage. And from the blood tests, they determined where they were in their menstrual cycle. The results were a strong correlation between fertility and skin exposure. The more likely they were to conceive tonight, the more flesh was on display. Their relationship status was almost irrelevant.

In all likelihood, not one of these women is making a calculated, rational decision to expose more skin tonight for this reason, and women being choosy in the way they are and for the reasons they are – both discussed above – even those dressed most provocatively may have failed to find anyone worthy to go home with, but this study does show I think at least one way in which our evolutionary legacy continues to influence our behaviour, whether we know it or not.

In a later post, I’ll explain why science can prove that there’s no such thing as bisexuality and why women genuinely don’t know what they want. If that doesn’t get you cross, then nothing will.

Part four is here.

TOM

I don’t think there is any evidence that a significant number of people are being harmed by choosing to go to alternative practitioners. There is undoubtedly a considerable morbidity and mortality arising from the side effects of drugs and the mistakes that happen in the conventional medicine system. Is the harm caused by inappropriate use of alternative medicine on the same scale?

Interesting. This is basically the Toyota defence isn’t it? “Until a lot more people are killed by our product, we don’t see the need to perform a recall.” Not really what I want my healthcare to be based on.

Your challenge to produce harm produced by alternative medicine “on the same scale” as that caused by evidence-based medicine does not make clear whether you want the same absolute number of corpses or the same level of morbidity per person treated. In either case, it is unlikely that I will be able to provide such evidence. In the first, less reasonable, case, despite my fears that alternative medicine fairy stories of miracle cures are distressingly seductive, it is obviously the case that almost everyone in Britain will be treated by conventional medicine at some point, but only a portion will seek alternative treatments. So even if they kill at the same rate, alternative medicine will be way behind. Even in the second, more reasonable, case, I doubt I will be able to meet this target since if someone is really sick and foolish enough to seek useless alternative therapies, it is likely that once they are at death’s door, they, or a relative, or someone will have the sense to take them to a proper doctor, and we can only hope they will be in time.

But just as we wouldn’t do without conventional medicine on the basis that a significant percentage of people who go into hospital will be killed simply because they went into hospital rather than because of the condition which brought them there, the question we should ask of homeopathic and other alternative remedies is not “what harm do they cause compared to other things in the world with the potential to do harm?” but “are they a net force for good?” or in other words “are we better off with or without them?” These calculations are not always easy to perform. Some people argue that the use of pesticides on fruits and vegetables contributes to deaths from cancer, and this is likely true. It is estimated that around 20 extra cancer deaths occur in the United States each year due to chemical pesticides. While this is a very small number (around 300 Americans die each year drowning in the bath by way of comparison), surely even 20 is too many. We should obviously get rid of these horrible carcinogens polluting our mealtimes. Alas, the immediate upshot of cutting back pesticide use would be to decrease farmers’ yields, which in turn would raise the price of their produce, which would in turn reduce the national consumption of fruits and vegetables, which would in turn increase the rate of cancers in the USA, probably adding 26,000 to the total (less the 20 who would no longer die because of exposure to pesticides). (Sources for these numbers on request).

So, let us ask what the harm caused by homeopathy is. I (and some of the commenters to this blog) have given you some examples of the horrendous consequences that can follow trusting that homeopathy will be efficacious in treating serious conditions. You say that you hope most people will have the sense to avoid magical treatments when their life is in danger, yet you seem quite sanguine at the prospect of people who are quite determined to erode this life-preserving common sense. Furthermore, the harm which homeopathy can cause is well-documented, by Simon Singh, through the campaign behind the “mass placebocide” or through this website dedicated to answering this very question. Note that Simon Singh makes the same connection that I do between homeopathy and mistrust of vaccinations. The body count due to recent refusals to vaccinate is easy to check.

Having agreed that harm from homeopathy is both possible and actual, we have to ask who it helps. Broadly, there are three kinds of people who might seek this kind of therapy.
• People suffering from serious conditions which require medical treatment. I am reassured that the Royal Homeopathic Hospital would refer these people, but still marvel at the cognitive dissonance required. Clearly, any people in this group run the serious risk of suffering quite unnecessary harm. For this group, the existence of alternative modalities is nothing but a negative. It will cause them to delay treatment.
• People suffering from self-limiting conditions which require little or no treatment in any case. These patients will not be directly harmed, except in the wallet. They will be spending money needlessly since their condition will improve on its own. This is a minor negative, but not in terms of health outcomes. It’s their money, you may argue, and they entitled to waste it however they please. Unfortunately, if they develop the belief that the alternative modality of their choice is effective in treating their minor self-limiting condition, then they may be more inclined to believe the more exotic claims made for this treatment and subsequently find themselves members of the first group. Thus, for this group also, the existence of alternative modalities is nothing but a negative.
• Finally, we come to the group which you have chosen to emphasise. Those suffering from chronic, non-life threatening conditions, for which no evidence-based treatment is offered or available. In a competitive marketplace, they are likely to get more sympathy from a quack than from a real doctor, and they may benefit in the short term from the (very powerful) placebo effect. They may even be permanently cured if they condition had no physical reality in any place (e.g. phantom limb sufferers or people who claim that mobile phone masts give them migraines). While I agree that some people in this group are made to feel better, I do not believe that this benefit is worth the cost, nor do I agree that the Royal Homeopathic Hospital (and other less scrupulous purveyors of fairy stories) is the best possible means of providing this kind of comfort. Relaxation techniques, improved diet, better trained GPs who understand the importance of providing emotional support to their patients and a better patient understanding of how psychosomatic illnesses affect us are all available and likely to be efficacious. You can probably add to that list.

So, no, I don’t believe that the harm done by homeopathy is on the scale of the harm done by conventional medicine. But conventional medicine does tremendous amounts of good which is absolutely unavailable anywhere else, whereas homeopathy does quite a lot of insidious harm, for only a little bit of good, almost all of which is available elsewhere.

Overall what makes me cross is big companies misleading people about important issues such as health. It isn’t just homeopaths who do this. Idiotic media celebrities like Gillian McKeith do the same thing. So do some drug companies. But lying to the general public about health is unlikely to have a positive effect on society, and institutions like the Royal Homeopathic Hospital, whether or not they cause harm themselves, make the lies of the unscrupulous so much more convincing. Campaigns like 1023 aim to provide more accurate information as a corrective to this – to help ensure that people do know that they need to be in hospital with severe chest or abdominal pain.

One of the recommendations made in the recent government Evidence Check was that homeopathy should have to be approved by NICE before being made available on the NHS. Do you think it would get NICE approval? On what grounds? If it wouldn’t, why should it be made available at no cost to patients when other more efficacious drugs are only available privately?

JOHN

I think the argument along the lines of ‘how many more people have to die before you admit I am right?’ is a bit over the top.

I think there are two areas where we are out of synch with each other. They concern the concepts of ‘health beliefs’ and ‘risk management’. I also have a problem with your relentless positivism. Science and logic and common sense are very valuable but there are other powerful forces that govern human beliefs and actions and they need to be understood rather than dismissed as simply foolish.

Risk management. Doctors deal with this every day. We are constantly having to decide whether to advise a patient to take a particular drug which has potential for good and for harm. This can be quantified to some extent. We can say, trials show that if you take aspirin your risk of a heart attack will be cut by X percent over ten years. There is also a risk that you will have a cerebral haemorrhage but the risk is much less so the odds are in favour of taking it. Often, when presented with this information, people say: but I’d rather not take any risk!  But this is impossible. It seems to be a hard concept to grasp. The other problem is that you can’t guarantee that taking the drug will have any benefit for that individual. The effect is only measurable on the population as a whole.

Health Beliefs. You argue that ‘the placebo effect’ can be more safely produced by doctors taking more time, being kind and sympathetic, being trained in psychology etc. But some people’s health beliefs are very physically based. They have very fixed ideas that only by swallowing a pill or having needles or massage or whatever can their bodily pains be relieved. Trying to argue people out of this is usually a waste of time. Often it’s based on personal experience or family traditions.

But I still think that for the overwhelming majority of people will be guided by conventional medicine when there is a really effective treatment available. I have yet to meet a patient who said, no, I’ll just have homeopathy etc. when it was a matter of life or death, or when I said, try this, we can really help you.

Maybe one can’t justify alternative medicine being paid for out of taxation or insurance. But I don’t think it will stop those people who believe in it from getting it privately if they have to. I don’t believe it should be banned by law because a few rather idiosyncratic people may wrongly choose it instead of conventional medicine when conventional medicine is in a position to prolong their lives or relieve their suffering.

That would be an abuse of their human rights. better to ban smoking if you must ban something. Or alcohol? Though, that has been tried.

And now I really have had enough of this subject. By all means have the last word. But after that,  can we talk about something else? How about euthanasia?

TOM

This seems a good place to end the conversation, as we are moreorless in agreement! I agree with everything you say about risk management and almost all of what you say about health beliefs.

I agree that for some people a physical intervention such as a pill, or a series of carefully placed needles, is required to trigger the placebo effect. You can’t argue someone in or out of the placebo effect – it isn’t a product of conscious decision-making.

I also agree that attempting to ban alternative medicine would not make it go away, any more than prohibition stopped people from drinking. Even regulating advertising of alternative medicine only encourages those who sell it to seek editorial promotion instead, which is more convincing than advertisements in any case.

So what do I want? Well, essentially just what you want – for everyone in the world to understand the difference between the claims made by evidence-based medicine and the claims made by magic-based medicine and so make informed health decisions. It’s just that you see very few people who get this wrong coming through your surgery and I read lots of blogs and listen to lots of podcasts which detail case after case, so we have formed very different views as to the scale of the problem. No doubt each of us has a somewhat skewed perspective.

The one area where I would be tempted to disagree would be on the subject of my “relentless positivism”. I am well aware that forces other than science and logic govern human beliefs and actions. However, I submit that to better understand these forces in an objective manner, the only option is to study these very forces with the tools of science and logic. But that’s not really what is under discussion here.

I imagine we’d boringly agree about euthanasia. Human dignity, relieving suffering and patients’ wishes all sometimes trump “first do no harm” but great care must be taken in exercising this option. Is that roughly your view too?

Part three is here.

TOM

Muddy waters? Not at all!

You say that you don’t see complementary/placebo medicine as competing with scientific medicine. However, not all placebo practitioners see it that way. Many peddlers of placebo cures directly attack what they sometimes term “allopathic” medicine as causing harm, arranged to make money for “big pharma” or who-knows-what other ills. Here’s a quick sampling of web pages and opinions which it took me about two minutes to find.

“Antibiotics kill bad as well as healthy bacteria. This results in weakening of immune system. Homeopathic medicines strengthen the immune system by building resistance to sickness. They do not disturb or hamper digestive system.”
http://www.otherhealth.com/research-scientific-validity-homeopathy/9877-modern-medicine-allopathy-homeopathy.html

“Allopathy’s strength lies in intervention. When you need a shot of penicillin, you need a shot of penicillin. When your body needs insulin, no therapy other than insulin injections will do. If surgery is required, then surgery is the solution. Allopathy’s weakness lies in the simple fact that removing the symptoms of a disease does not necessarily remove the cause of the disease. Its greatest weakness is that many of its cures are killing people. One reason many people have left conventional medicine for healthier alternatives is that death is not an acceptable side effect.”
http://www.mnwelldir.org/docs/therapies/what_is.htm

“[The World Health Organisation] wants to remain ignorant about AIDS, because it is under the control of the big Multinational Companies manufacturing the so–called HIV–detection kits and the highly toxic drugs like AZT, which products they must sell by any means to make the big bucks.”
http://www.wonder-cures.com/art8.htm

Now, it’s easy for you and me to dismiss these as the ravings of cranks, and indeed you then say “you think most people are aware that they [evidence-based and alternative medicine] are different in conception”. Presumably you think this is important. If people are aware that antibiotics are a sensible (although not a guaranteed) treatment for pneumonia but that homeopathic remedies are unsuitable, then they will steer clear of them – despite the fact that they are readily available.

How does it help this vital distinction between evidence-based and placebo medicine to be maintained if placebo medicine shares shelf-space with evidence-based cures in Boots? If NHS doctors provide imaginary treatments on request? If evidence-based medicine is offered side-by-side with placebo medicine, as birthing pools are provided side-by-side with epidurals in maternity wards? How can the lines not be blurred in patients’ minds? And do you not share my concern about the possibility of harm once these lines are successfully blurred? This is where the muddy waters really are, I believe.

Yes, there is no market for herbs on broken legs, but there is a big market for homeopathy which is no more magical, but which presents a more credible face to the western world. Homeopathic pills look like medicines (which partly accounts for their effectiveness, although studies show that saline injections – a more impressive intervention – can be even more effective in pain relief for example) and so they appeal to a moderately medically-literate audience. But that appeal depends on blurring the distinction which you identified. And it works – the market for homeopathy in the UK is estimated at £30m annually (£4m on the NHS). For complementary medicine as a whole it is £1.6bn. That’s a lot of money to spend on magic.

I agree, that if it were the case that all promoters of homeopathic medicine (and other placebo interventions) were eager to direct their patients towards evidence-based interventions for more serious or urgent situations (regardless of the inevitable cognitive dissonance that this requires), then they would do considerably less harm. But your personal experience of this kind of co-operation happening in China or on the NHS doesn’t change the fact that it is not the norm. When researchers visit high street homeopathic vendors, they are prescribed useless sugar pills as a malaria prophylaxis and told not to bother with evidence-based immunisation. When patients visit websites for information about homeopathy, they may read information which presents evidence-based medicine as a cure which is worse than the disease. When practitioners of placebo medicine are criticised in the press, they often attempt to silence their critics by legal means, as happened recently to Simon Singh, heedless of the fact that open scientific debate is essential for determining best options for patient care.

The upshot of all of these behaviours could be and is that patients die who might well have lived had they not been fed this misinformation. The further consequence is that it becomes easier for evidence-free attacks on mainstream medicine, such as the anti-vaccination campaign, to take hold in the public consciousness. This seems to me like far too high a price to pay for the temporary alleviation of chronic pain in some patients, or the illusion of relief from self-limiting conditions for others.

We know that pneumonia kills, but that it can be effectively treated by antibiotics. We know that a lot of people are unaware of the fact that homeopathy is a useless treatment for pneumonia, because homeopathic treatments are readily available, and if no-one thought they would be effective, market forces would ensure that – like herbs for broken legs – they would be nowhere to be found. People who believe that homeopathic remedies will treat their pneumonia will likely die. Homeopaths have a strong vested interest in maintaining this belief. Homeopathic pills in Boots and the presence of an institution such as the Royal London Homeopathic Hospital are very effective in helping to maintain this belief.

Your initial question to me was “why are you so cross about this?” My question to you is “why aren’t you?”

JOHN

The reason I am not cross about it is that I don’t think there is any evidence that a significant number of people are being harmed by choosing to go to alternative practitioners. Do you know of any?  Its true that these advertisements appear to be very misleading, but I think people have enough sense to know  that they need to be in hospital with severe chest or abdominal pain and that they need a surgeon for a broken leg.

They go to the alternative practitioners only when they have discovered that they have the kind of symptoms which are painful or distressing but not due to any disorders that conventional medicine can help except by support and the doctor’s continuing interest  and concern. Sadly,  that may be more forthcoming from a homeopath.

And, as I have said there is something about these  miracle cures that has a very strong appeal to human nature. I’m not sure that one can or should legislate against it unless you can show that harm has resulted on a significant scale. What is significant? Well, there is undoubtedly a considerable morbidity and mortality arising from the side effects of drugs and the mistakes that happen in the conventional medicine system.   Is the harm caused by inappropriate use of alternative medicine on the same scale?

Part two is here

TOM

I’ll keep this as brief as I can.

Parts of your reply misrepresent my position slightly. I’d like to clear up any misconceptions.

I don’t equate evidence with certainty. Absolutely, we can be less sure than we would ideally like that a given intervention will be effective in a given case, but we always have an evidence base on which to make such judgments – even if the best we can say is “this is a wildly experimental treatment which stands as good a chance of curing your cancer as it does of killing you on the spot, but we’ve run out of other things to try – what do you say?” If this is a lottery, it’s one where we can often buy an awful lot of tickets.

Thus, I continue to insist that everything is split into two categories. A physician can recommend a treatment because there is evidence to suggest that it will be effective or can ignore the evidence which shows that a treatment is no better than placebo and prescribe it anyway. A physician can honestly tell a patient that the evidence is inconclusive, or dishonestly claim results which are not supported by data of any kind.

The other slippery issue is that of false claims. You approve of the wording on the Homeopathic Hospital’s website regarding Iscador, but I’m not sure you are looking at this website the way a patient might. Here’s a page from a website all about Iscador.

Here we read that “one of the primary functions of Iscador^® is that it stimulates parts of the immune system that can slow the growth of cancer cells”. This, as we know, is rubbish. On the same website, there is a link to a single study, published in a Complementary Medicine Journal which purports to show a significant benefit to cancer sufferers using this preparation. However, as we have already seen, a review of all the available literature shows that overall there is no good evidence that Iscador has this effect. This is the usual pattern. Evidence-based (or science-based) medicine which reviews all the available evidence, and people with a pill to sell (herbal or pharmaceutical) who pick only the studies they like and ignore the rest.

Now consider the effect on a patient who may have seen these other claims made for Iscador’s magical cancer-healing powers, coming across Iscador on a National Health Service website. It isn’t the details of the mode of action that stick in the mind – it’s the key message MISTLETOE CURES CANCER. And this message is reinforced, not contradicted, by the product’s availability through an apparently prestigious and trustworthy source. So while the NHS might stop short of actually saying “mistletoe cures cancer”, it ends up delivering that message just the same.

It is at least partly for this reason that the Ten23 campaign is targeting Boots. When homeopathic preparations are seen side-by-side on the shelf with active pharmaceuticals in the country’s largest and most-trusted pharmacy, it is almost inevitable that patients will get the wrong impression (this is reinforced by dire warnings on the sides of the bottles). So, it becomes impossible to clearly send a message that homeopathy will not cure your cancer, is not a suitable defence against malaria, will not cure your child of eczema and so on, and the result is that people believe the hype, and sometimes that belief turns out to be deadly.

My feeling is that placebo cures possibly do have a role in treating chronic conditions such as back pain, may even have a role in treating minor self-limiting conditions although this is more likely to be simply a waste of everyone’s time,* but are a danger as soon as they are let near anything remotely life-threatening. With a powerful lobby that can’t bring itself to say “for god’s sake get proper medicine if you feel really poorly,” the only answer is to try and destroy the credibility of these interventions as much as possible, or stand by as greedy corporations and misguided practitioners continue heedless of the harm they cause.

So it isn’t that homeopathy on the NHS is itself prescribed in a cavalier or life-threatening way, rather that this activity is an enabler, enhancing the credibility of others with fewer ethics or less regard for evidence, and also fuelling the fires of hysterical media coverage of things like Andrew Wakefield’s infamous MMR paper. Is public demand for medicalised quick-fixes a good enough reason to accept this corrosion of public standards of evidence? I don’t think it is.

You asked the excellent question – can you have medicine without quackery? I don’t know if you can. But I do know that mainstream medicine has no business flattering the quacks.

One final question for you. Many churches pray for people with life-threatening illnesses and many people feel happy that people are praying for them. What if this were offered as a service on the NHS? Is government-sponsored prayer also something you would endorse?

* Caveat – when I have a sniffle, I’m perfectly well aware that no matter what I do it will probably last 3-4 days, but I prefer Lemsip to a homebrewed hot lemon drink because the fact that Lemsip tastes a bit medicine-y makes me feel better. The placebo effect is also present with pharmaceutical interventions of course.

JOHN

I don’t see complementary medicine (or if you prefer ‘placebo medicine’) as competing with scientific medicine. I think most people are aware that they are different in conception and that for some major illnesses or accidents only science will deliver. Very few people put herbs on broken legs these days. There would be no demand for it on the NHS.

Whether there would be a demand for prayers for healing on the NHS I don’t know but it might catch on and save a lot of money currently spent on visits to A and E.

When I was in China last year, I was interested to see that some of the hospitals and clinics we visited  had Western scientific medicine  and TCM ( traditional Chinese Medicine) departments running side by side. The patients chose which one to go to, but if the doctor they went to initially thought they had got it wrong they were cross-referred to the other wing.  So the two approaches can co-operate.

That’s all I  have to offer for now. I hope I have muddied the waters a bit so you can get to work clearing them again.

Part one is here…

TOM

Let’s start by enlarging the list of things we both agree on.

I agree that placebo pills cause no direct harm whereas absolutely any active chemical introduced into the body has at least the potential for harm, even those which have long been associated with health and well-being; there is, for example, some evidence that routinely taking vitamin supplements when not indicated may have negative health outcomes.

I also agree that homeopathy and other alternative modalities make some people feel better but regret that the only way to safeguard the efficacy of the intervention is to mislead patients as to what is going on. It is important that the patient believes that the pill, needle, shamanic ritual or whatever will be efficacious. When prescribing even (or especially) a very risky treatment like radiotherapy, a physician can explain the potential costs and benefits, based on a large body of evidence, in order that the patient can make an informed choice. Prescribing placebo treatments as if they are effective removes that informed choice, but telling the patient “this won’t work” is a self-fulfilling prophecy, so homeopaths – whether or not they are themselves deluded – are deceiving their patients.

Of course, if patients want it and are made to feel better, why should we worry about removing informed choice? I do have an answer to this question, but I don’t want to get ahead of myself. Let me finish responding to your points first.

You write that you think that homeopathy is an appropriate use of public funds to treat chronic conditions for which no effective evidence-based treatment exists, and it may be that the London Homeopathic Hospital does restrict itself to interventions in those cases. It may also be that all of the Homeopaths working there are medically qualified (I wasn’t aware of this – do you have a reference?).

But it is not true, despite the name, that within the tranquil environment of the LHH, homeopathy is the only evidence-free service available. A quick look at their website reveals that they are also happy to provide Reiki, Acupuncture, Reflexology and Iscador – a new one on me – which we learn is “a preparation of mistletoe, which enhances immune system responses.” Bearing in mind that this is on a page titled Complementary Cancer Care Programme, doesn’t this worry you at all? Do you really want your patients believing that mistletoe will cure their cancer? Who benefits from sustaining this belief, except those who have “Iscador” to sell?

Only one passage in your very thoughtful email stood out as something I would really take issue with – this one: “Every form of medical practice has its own philosophy, including evidence based medicine, which, by the way is not always as reproducible in an ordinary community setting as it is under strict experimental conditions.  Even EBM in most cases only offers a probability of a cure or improvement: a significant proportion of those treated will not benefit at all. Some will be harmed.” Let me begin with your last point. Yes, every active treatment has a risk, but as I’ve said EBM enables patients and physicians to make informed choices. It is possible to do great harm with the best intentions, which is way we must hold evidence in such high regard. Are you familiar with the on-going libel case which the British Chiropractic Association recently brought against the journalist Simon Singh? This case illustrates one of my chief reasons to want to see homeopathy and other sham treatments no longer flattered by government support.

You warn me that lab trials are not always replicated in the real world. But my definition of “evidence” is not so narrow as to only include clinical trials (although I still regard a large, prospective, double-blind, randomised trial as the gold standard for determining whether and to what extent a given intervention will be effective). We can certainly obtain data from retrospective analyses, and from seeing what actually happens in the real world. Sometimes these results are surprising, but EBM means we can’t ignore results which sound wrong to us or which go against long-cherished notions.

For example, the United States Preventative Services Task Force recently altered its recommendations regarding breast cancer screening. In their report was the rather surprising and controversial finding that self-examination appears to have no effect whatsoever on breast cancer death rates, but that it can create a lot of unnecessary fear and alarm. The emphasis (at least in the States) is now on breast awareness – has anything in your breasts changed recently? – rather than teaching women to perform rigorous and regular self-examinations. Many people object to this advice on the basis that they have a belief that breast self-exams are important, or that they have a story about someone who found a lump during such an exam, and whose life may have been saved thanks to the operation which swiftly followed. This doesn’t alter the evidence which is that such exams make no difference to health outcomes, and we take lives in our hands if we allow our preconceptions and biases to defeat the evidence.

Where we really part company is when you describe different forms of medical practice as having their own philosophies. It sounds to me as if you are claiming that each of these philosophies is equally good, and the only real difference is in the philosophical starting point, EBM being no better and no worse than homeopathy. While that might be a useful diplomatic position to take, I simply can’t accept it, any more than I would accept Apartheid (or any one of a number of other atrocities) as a mere difference in political philosophy.

While it is true that there is a bewildering array of supposedly therapeutic modalities available, they all slot cleanly into one of two categories – based on evidence or not based on evidence. Anything not based on evidence is based to some extent on subjectivity and personal choice. A practitioner who accepts Reiki but rejects Iridology has no objective basis for making this choice. They simply prefer Reiki and allow confirmation bias to do the rest.

When the system is working (and god knows it doesn’t always) evidence-based medicine prevents even the most enthusiastic champion of a particular intervention from being able to claim that it works when it doesn’t. We know that Dimebon is ineffective for treating Alzheimer’s and so it will not be prescribed. We know that mistletoe will not cure cancer, but at the Royal London Homeopathic Hospital, they will apparently provide it to anyone who asks, and at the taxpayer’s expense.

This means that proponents of non-evidence based modalities have no choice but to duck the issue, or misleadingly cherry-pick from the data in order to create a false picture – which is exactly what the select committee experienced when it asked notable homeopaths to give evidence. Who benefits from this corruption of the scientific method? Isn’t this exactly the “denying the validity of science itself” which you hoped wouldn’t happen? Why does homeopathy get a pass? Because it does no harm? I’m not so sure that’s true.

You began by saying that you wanted to include in our discussion the whole context of treatment, and here again I agree enthusiastically. So, while we both know that a sugar pill in itself is guaranteed harmless, we also know that we are talking about a complicated cultural phenomenon which is not limited to a person taking a pill, and therefore nor is homeopathy’s reach confined to people suffering from chronic back pain. Nor is it always the case that homeopaths advise people who need conventional treatment to go and get it. In 2006, a survey performed by Sense about Science which was followed up by Newsnight found that every high street homeopath visited by a researcher about to travel to a malaria-infested country was given useless homeopathic quinine and none were told to visit a GP or a travel clinic or even to buy a mosquito net.

How are “responsible” homeopaths supposed to respond to this? The Royal Homeopathic Hospital did its best to smack down this irresponsible behaviour, but what are they really saying? “We all know the sugar pills don’t really work, so don’t for goodness sake go giving them to someone who actually needs medicine.” What would the True Believers make of that!? By beginning from a position which isn’t supported by evidence, “responsible” homeopaths are now in an impossible bind. They either have to defend the magic to the hilt, or admit that it’s all a load of imaginative nonsense. Not surprisingly, they hem and haw and waffle and evade, they dissemble in front of parliamentary select committees, and essentially they let the harm continue, such as in the horrifying case of the Australian couple who attempted to treat their baby daughter’s eczema with homeopathy until eventually she died after months of excruciating pain (they are now in prison).

So even if we are happy to divide quackery into good (prescribed by responsible physicians in tandem with evidence-based treatments where appropriate) and bad (prescribed willy-nilly by people with little or no medical training, and cheerfully offered as a substitute for evidence-based treatments, or non-medicalised interventions) – the question must still be asked can you have one without the other? This line of argument will eventually bring us back to vaccines, but I feel I should stop here, having written quite a lot already, and get another response from you.

JOHN

Can we aim for something a little more concise? I don’t have time for a discussion in this depth!

I am very pleased that you are taking such an interest in medicine and medical ethics. I note that you are a very much a postitivist in your approach and have no time for post-modernist ideas of different beliefs having equal validity! Well I don’t know that I have in extreme cases where it is clear that science has the best solution (e.g. antibiotic for pneumonia or angioplasty for blocked artery).

However, there are many grey areas where all is not as certain as one would like. As I have already mentioned, the much venerated ‘gold standard’ trial doesn’t simply distinguish effective from ineffective interventions. When the effect is really clear you dont need a trial. What we usually get is a statistical result showing that the probability of an effect is greater than could be due to chance alone. This means that some patients will do well but others won’t. The NNT (number needed to treat) may be 4 or 5 for a good drug or 10 or more for many others. So we can’t promise our patients that even a gold standard treatment will do them any good (or no harm). It’s a game of roulette. No one can tell what will happen to any individual.

It is unfortunately not the case that everything slots neatly into two categories, evidence-based or not. Evidence can be strong or weak. Evidence is continually being modified or even contradicted. It doesn’t apply to all individuals. So I tell my patients who ask me if complementary treatments are any good, that some patients find them helpful but others don’t. Same difference.

I agree that it would be dishonest to say that ‘a sugar pill’ will have a biochemical effect. But you can say that, some practioners believe that the way this pill was made can make a difference to the ability of some people to cope with an illness that conventional medicine has not been able to help very much.

I agree, of course, that no one should make false claims about these remedies. The information for cancer patients from the Homeopathic Hospital seems to me to make it very clear that these treatments are to help you cope with the illness and its definitive treatment rather than to act alone. I dont know about the eczema girl who died, it is often difficult to tell from these accounts exactly what happened. But no responsible doctor would have advised the parents to ignore conventional medicine. I don’t think this would happen at the Homeopathic Hospital. I went on a visit to the place and met the medical director Dr Sara Eames who was very clear about this. She also told us that all the medical staff have medical qualifications.

Can you have good quackery without bad? Can you have medicine without quackery? I don’t think you can have medicine based on evidence alone. There isn’t enough evidence for one thing. And people are often have health beliefs that are so firm that no amount of statistical information will influence them. The placebo effect, if you want to call it that will often make something happen. If you prefer you can call it the effects of thoughts and feelings being processed by different brain areas resulting in changes in pain perception, sensation, reduced muscular stiffness, improved mood and reduced anxiety etc. etc.

Enough for now!