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philosophy
This was the title of a meeting organised by the Bristol University Atheist Agnostic and Secular Society on 1st November. The meeting wasn’t recorded, but here is (more or less) what I said.
I’m not quite sure why I’m here, because the fantasies of religion seem to me much like the fantasies of quack medicine, not only morally offensive, but also simply boring. Fruitless speculations about the existence of gods is about as useful a way to spend time as fruitless speculations about whether there really are fairies at the bottom of your garden.
Of course people are free to believe in any daft thing they want, as long as it doesn’t harm anyone else. The problem is that daft beliefs about religion, just like daft beliefs about medicine, do harm other people. I suppose it’s my job to point out that neither religion nor philosophy are likely to allow you to understand the world, whereas science has, at least, got a chance of doing so. It has made a small start already.
What I like about science is that it is undogmatic. When the facts change you are forced to change your mind. If the facts contradict your theory, then your theory is wrong.
Very often, you have simply to say “I don’t know”. In contrast, religious people virtually never change their minds and very rarely say they “don’t know”. They invent pseudo-explanations, like “god did it”, for just about anything, and justify it with quotations from holy books. The holy books are so inconsistent, often downright weird, that you can pick a citation that justifies whatever your opinion was in the first place. You might as well cite a book of magic spells.
I’d maintain that philosophers of science have contributed very little of substance to the conduct of science, but I’ll miss that bit out because I wrote about it last week,.
Dr Baggini, among others, has claimed that the “new atheists” are too strident, and that they only antagonise moderate atheists (see The New Atheist Movement is destructive, though there is something of a recantation two years later in Religion’s truce with science can’t hold).
I disagree, for two reasons.
Firstly, people like Richard Dawkins are really not very strident. Dawkin’s book, The God Delusion, is quiet and scholarly. It takes each of the arguments put forward by religious people, and dissects them one by one. It’s true that, having done this, he sets forth his conclusions quite bluntly. That seems to me to be a good thing. If your conclusions are stifled by tortuous euphemisms, nobody takes much notice. Just as in science, simple plain words are best.
The second, and more important, reason that I like Dawkin’s approach is that I suspect it’s the only approach that has much effect. There is a direct analogy with my own efforts to stop universities giving BSc degrees in subjects that are not science. Worse, they are actively anti-science. Take for example, homeopathy, the medicine that contains no medicine. I started by writing polite letters to vice chancellors. Usually they didn’t even have the courtesy to reply. All efforts to tackle the problem through the “proper channels” failed. The only thing that has worked was public derision. A combination of internal moles and Freedom of Information Act requests unearthed what was being taught on these courses. Like Westminster’s assertion that “amethysts emit high Yin energy”. Disclosure of such nonsense and headlines like
“Professor Geoffrey Petts of the University of Westminster says they “are not teaching pseudo-science”. The facts show this is not true
are certainly somewhat strident. But they have worked. Forget the proper channels if you want results. Mock what deserves to be mocked.
Religion is often immoral
When a pair of besuited Mormons knock on the front door, there are two reactions. Most people hide under the kitchen table. I don’t. I invite them in. It usually goes something like this. “why don’t you believe in god?”. To which I respond, “I don’t believe in god on moral grounds. All religions that I have encountered teach immorality”
This response is greeted with incredulity and indignation. You may think, is a bit strong, so let’s have some examples. The bible says (amongst many contradictory things)
Deuteronomy , chapters 7 & 20. and Joshua, chapters 6, 8, 10, 11, 14, etc.: After wandering in the desert for four decades, God ordered the Hebrews to invade the "promised land" and totally exterminate "the Hittites, and the Amorites, the Canaanites, and the Perizzites, the Hivites and the Jebusites"leaving "alive nothing that breathes." They were to fight and kill the soldiers of these groups, and then murder the defenseless elderly, women, youths, children, infants, and newborns. The book of Joshua records the progress of the genocide, city by city:
Deuteronomy 21
20. And they shall say unto the elders of his city, This our son is stubborn and rebellious, he will not obey our voice; he is a glutton, and a drunkard.
21. And all the men of his city shall stone him with stones, that he die: so shalt thou put evil away from among you; and all Israel shall hear, and fear.
and the Koran says
“The woman and the man guilty of adultery or fornication—flog each of them with hundred stripes: Let no compassion move you in their case, in a matter prescribed by God, if ye believe in God and the last day.”[Quran 24:2] “
If these aren’t deeply immoral, I don’t know what is. This gratuitous cruelty isn’t just Old Testament either. This is what persuaded me that religion is bad.
When I was about 15 I went to a summer camp which turned out to be run by christian evangelists (my parents swore they didn’t realise that it was a brain-washing camp). I was converted and became rather earnest. Then, at 18, I met a nurse. Being on Merseyside, she was Irish. And being 18, I was rather interested in sex. The price of sex was to go with her to mass, so of course I went. It was Easter and they were doing the Twelve Stations of the Cross. I still recall watching this, with mounting horror. The priests were just enjoying it too much. It was almost like a sado-masochistic orgy. The priests seemed to be almost masturbating. It was simply sick. Quite revolting.
Once, after walking in the Dolomites, I wrote to the Italian Tourist Authority to complain that my holiday was spoiled because every time I got to the top of a mountain, I was greeted with a scene of graphic torture (a crucifix). It is very offensive to any normal human.
Of course, since then, it’s turned out that a large number of priests were not just enjoying the torture in their heads, but had been acting out their nasty fantasies through rape of real children. And that the Church (including the present pope) had gone to great lengths to conceal their activities from m the public and from the police.
The constant emphasis on guilt is horrible for adults. But telling happy young children that they are guilty sinners is obnoxious. It is a form of child abuse. And catholic schools that decorate classrooms with scenes of torture corrupt young minds. Indoctrinating children in one particular sect of one religion are not part of a civilized society. It promotes misunderstanding and prejudice between one child and another. This sort of divisive brainwashing is ghastly.
Ludicrously, when you pass 18, the law reverses itself. Up to the age of 18 you are encouraged by moral politicians (you know, like Blair and Gove) to promote religious segregation but once you pass 18, that sort of behaviour would, very properly, be illegal. The Universities Tests Act (1871) made it illegal for a university discriminate on grounds of religion, as governments actively encourage schools to do. (The Act was passed, of course, to bring Oxford and Cambridge up to the standards set by UCL in 1826.)
Then, of course, there is the church’s contribution to the spread of AIDS, by telling direct lies about condoms. The list goes on and on.
And these people want to tell us about morals? You must be joking.
When Napoleon mentioned to the great mathematician, Laplace, that God is not mentioned in the Me’chanique ce’leste, Laplace replied, " Sire, I did not need that hypothesis." When Napoleon later reported this reply to Lagrange, the latter remarked, "Ah, but that is a fine hypothesis. It explains so many things."
History doesn’t relate whether Lagrange’s comment was deeply ironical, but I like to think it was. It hits the nub of the problem. Religion explains nothing whatsoever, just muddles the ideas, and replaces one unknown with another.
At the time of the Reformation, Sir Thomas More was fond of burning heretics at the stake (merely possessing a bible in English was enough to get you tortured to death). .The protestants were no better, of course: they eventually decapitated More. But it won’t do to say that these things happened in the 16th century. In the 20th Century the pope declared the heretic-burner to be saint (one of the curious bits of make-believe that catholics seem to enjoy). Worse still, in 2000, Pope John Paul II declared Thomas More to be the “heavenly patron of statesmen and politicians” (whatever that means).
And of course it still goes on. Catholics and protestants kill each other. Sunnis and Shias kill each other. It’s characteristic of organisations whose beliefs are based on myths to be deeply aggrieved by people whose myths differ in some trivial detail. It happens in alternative medicine too. It’s all summed up in the "religious joke of the year".
I was walking across a bridge one day, and I saw a man standing on the edge, about to jump. I ran over and said: "Stop. Don’t do it."
"Why shouldn’t I?" he asked.
"Well, there’s so much to live for!"
"Like what?"
"Are you religious?"
He said, "Yes."
I said, "Me too. Are you Christian or Buddhist?"
"Christian."
"Me too. Are you Catholic or Protestant?"
"Protestant."
"Me too. Are you Episcopalian or Baptist?"
"Baptist."
"Wow. Me too. Are you Baptist Church of God or Baptist Church of the Lord?"
"Baptist Church of God."
"Me too. Are you original Baptist Church of God, or are you Reformed Baptist Church of God?""Reformed Baptist Church of God."
"Me too. Are you Reformed Baptist Church of God, Reformation of 1879, or Reformed Baptist Church of God, Reformation of 1915?"
He said: "Reformed Baptist Church of God, Reformation of 1915."
I said: "Die, heretic scum," and pushed him off.
In a nutshell, my objection to religion is that, with occasional honourable exceptions, it spreads immorality and violence.
Of course non-religious people can be just as immoral and violent, but, in the words of Stephen Weinberg:
"for good people to do evil things, it takes religion."
Is there hope for something better?
It’s pretty clear that as education spreads, religion dies. The process is well-advanced in the west, in every country apart from the USA, but in the USA religion is just another business, devoted to extracting money, mostly from the poor, and supporting the extreme right wing parties and military adventurism.
We shouldn’t be too smug about Islam either. Admittedly I was slightly taken aback when a second year undergraduate, on duty at an Islamic exhibition at UCL, told me that "when Islam came to power in the UK I would be executed" (and then asked for my name). But it’s little more than 100 years since we stopped whipping people and people were still being hanged in my lifetime. My guess is that in another few hundred years, Islam will catch up. It will become gradually less cruel and women will, bit by bit, come to be treated as human beings. But once that happens, Islam will start to die out altogether, just as Christianity has (almost) done in the West.
So, in the words of the atheist bus campaign.
"There is probably no God. Now stop worrying and enjoy your life."
Follow-up
In the questions after the talk, I was spurred into saying
Religion is what we had before the enlightenment
I have in the past, taken an occasional interest in the philosophy of science. But in a lifetime doing science, I have hardly ever heard a scientist mention the subject. It is, on the whole, a subject that is of interest only to philosophers.
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It’s true that some philosophers have had interesting things to say about the nature of inductive inference, but during the 20th century the real advances in that area came from statisticians, not from philosophers. So I long since decided that it would be more profitable to spend my time trying to understand R.A Fisher, rather than read even Karl Popper. It is harder work to do that, but it seemed the way to go.
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This post is based on the last part of chapter titled “In Praise of Randomisation. The importance of causality in medicine and its subversion by philosophers of science“. A talk was given at the meeting at the British Academy in December 2007, and the book will be launched on November 28th 2011 (good job it wasn’t essential for my CV with delays like that). The book is published by OUP for the British Academy, under the title Evidence, Inference and Enquiry (edited by Philip Dawid, William Twining, and Mimi Vasilaki, 504 pages, £85.00). The bulk of my contribution has already appeared here, in May 2009, under the heading Diet and health. What can you believe: or does bacon kill you?. It is one of the posts that has given me the most satisfaction, if only because Ben Goldacre seemed to like it, and he has done more than anyone to explain the critical importance of randomisation for assessing treatments and for assessing social interventions.
Having long since decided that it was Fisher, rather than philosophers, who had the answers to my questions, why bother to write about philosophers at all? It was precipitated by joining the London Evidence Group. Through that group I became aware that there is a group of philosophers of science who could, if anyone took any notice of them, do real harm to research. It seems surprising that the value of randomisation should still be disputed at this stage, and of course it is not disputed by anybody in the business. It was thoroughly established after the start of small sample statistics at the beginning of the 20th century. Fisher’s work on randomisation and the likelihood principle put inference on a firm footing by the mid-1930s. His popular book, The Design of Experiments made the importance of randomisation clear to a wide audience, partly via his famous example of the lady tasting tea. The development of randomisation tests made it transparently clear (perhaps I should do a blog post on their beauty). By the 1950s. the message got through to medicine, in large part through Austin Bradford Hill.
Despite this, there is a body of philosophers who dispute it. And of course it is disputed by almost all practitioners of alternative medicine (because their treatments usually fail the tests). Here are some examples.
“Why there’s no cause to randomise” is the rather surprising title of a report by Worrall (2004; see also Worral, 2010), from the London School of Economics. The conclusion of this paper is
“don’t believe the bad press that ‘observational studies’ or ‘historically controlled trials’ get – so long as they are properly done (that is, serious thought has gone in to the possibility of alternative explanations of the outcome), then there is no reason to think of them as any less compelling than an RCT.”
In my view this conclusion is seriously, and dangerously, wrong –it ignores the enormous difficulty of getting evidence for causality in real life, and it ignores the fact that historically controlled trials have very often given misleading results in the past, as illustrated by the diet problem.. Worrall’s fellow philosopher, Nancy Cartwright (Are RCTs the Gold Standard?, 2007), has made arguments that in some ways resemble those of Worrall.
Many words are spent on defining causality but, at least in the clinical setting the meaning is perfectly simple. If the association between eating bacon and colorectal cancer is causal then if you stop eating bacon you’ll reduce the risk of cancer. If the relationship is not causal then if you stop eating bacon it won’t help at all. No amount of Worrall’s “serious thought” will substitute for the real evidence for causality that can come only from an RCT: Worrall seems to claim that sufficient brain power can fill in missing bits of information. It can’t. I’m reminded inexorably of the definition of “Clinical experience. Making the same mistakes with increasing confidence over an impressive number of years.” In Michael O’Donnell’s A Sceptic’s Medical Dictionary.
At the other philosophical extreme, there are still a few remnants of post-modernist rhetoric to be found in obscure corners of the literature. Two extreme examples are the papers by Holmes et al. and by Christine Barry. Apart from the fact that they weren’t spoofs, both of these papers bear a close resemblance to Alan Sokal’s famous spoof paper, Transgressing the boundaries: towards a transformative hermeneutics of quantum gravity (Sokal, 1996). The acceptance of this spoof by a journal, Social Text, and the subsequent book, Intellectual Impostures, by Sokal & Bricmont (Sokal & Bricmont, 1998), exposed the astonishing intellectual fraud if postmodernism (for those for whom it was not already obvious). A couple of quotations will serve to give a taste of the amazing material that can appear in peer-reviewed journals. Barry (2006) wrote
“I wish to problematise the call from within biomedicine for more evidence of alternative medicine’s effectiveness via the medium of the randomised clinical trial (RCT).”
“Ethnographic research in alternative medicine is coming to be used politically as a challenge to the hegemony of a scientific biomedical construction of evidence.”
“The science of biomedicine was perceived as old fashioned and rejected in favour of the quantum and chaos theories of modern physics.”
“In this paper, I have deconstructed the powerful notion of evidence within biomedicine, . . .”
The aim of this paper, in my view, is not obtain some subtle insight into the process of inference but to try to give some credibility to snake-oil salesmen who peddle quack cures. The latter at least make their unjustified claims in plain English.
The similar paper by Holmes, Murray, Perron & Rail (Holmes et al., 2006) is even more bizarre.
“Objective The philosophical work of Deleuze and Guattari proves to be useful in showing how health sciences are colonised (territorialised) by an all-encompassing scientific research paradigm “that of post-positivism ” but also and foremost in showing the process by which a dominant ideology comes to exclude alternative forms of knowledge, therefore acting as a fascist structure. “,
It uses the word fascism, or some derivative thereof, 26 times. And Holmes, Perron & Rail (Murray et al., 2007)) end a similar tirade with
“We shall continue to transgress the diktats of State Science.”
It may be asked why it is even worth spending time on these remnants of the utterly discredited postmodernist movement. One reason is that rather less extreme examples of similar thinking still exist in some philosophical circles.
Take, for example, the views expressed papers such as Miles, Polychronis and Grey (2006), Miles & Loughlin (2006), Miles, Loughlin & Polychronis (Miles et al., 2007) and Loughlin (2007).. These papers form part of the authors’ campaign against evidence-based medicine, which they seem to regard as some sort of ideological crusade, or government conspiracy. Bizarrely they seem to think that evidence-based medicine has something in common with the managerial culture that has been the bane of not only medicine but of almost every occupation (and which is noted particularly for its disregard for evidence). Although couched in the sort of pretentious language favoured by postmodernists, in fact it ends up defending the most simple-minded forms of quackery. Unlike Barry (2006), they don’t mention alternative medicine explicitly, but the agenda is clear from their attacks on Ben Goldacre. For example, Miles, Loughlin & Polychronis (Miles et al., 2007) say this.
“Loughlin identifies Goldacre [2006] as a particularly luminous example of a commentator who is able not only to combine audacity with outrage, but who in a very real way succeeds in manufacturing a sense of having been personally offended by the article in question. Such moralistic posturing acts as a defence mechanism to protect cherished assumptions from rational scrutiny and indeed to enable adherents to appropriate the ‘moral high ground’, as well as the language of ‘reason’ and ‘science’ as the exclusive property of their own favoured approaches. Loughlin brings out the Orwellian nature of this manoeuvre and identifies a significant implication.”
If Goldacre and others really are engaged in posturing then their primary offence, at least according to the Sartrean perspective adopted by Murray et al. is not primarily intellectual, but rather it is moral. Far from there being a moral requirement to ‘bend a knee’ at the EBM altar, to do so is to violate one’s primary duty as an autonomous being.”
This ferocious attack seems to have been triggered because Goldacre has explained in simple words what constitutes evidence and what doesn’t. He has explained in a simple way how to do a proper randomised controlled trial of homeopathy. And he he dismantled a fraudulent Qlink pendant, purported to shield you from electromagnetic radiation but which turned out to have no functional components (Goldacre, 2007). This is described as being “Orwellian”, a description that seems to me to be downright bizarre.
In fact, when faced with real-life examples of what happens when you ignore evidence, those who write theoretical papers that are critical about evidence-based medicine may behave perfectly sensibly. Although Andrew Miles edits a journal, (Journal of Evaluation in Clinical Practice), that has been critical of EBM for years. Yet when faced with a course in alternative medicine run by people who can only be described as quacks, he rapidly shut down the course (A full account has appeared on this blog).
It is hard to decide whether the language used in these papers is Marxist or neoconservative libertarian. Whatever it is, it clearly isn’t science. It may seem odd that postmodernists (who believe nothing) end up as allies of quacks (who’ll believe anything). The relationship has been explained with customary clarity by Alan Sokal, in his essay Pseudoscience and Postmodernism: Antagonists or Fellow-Travelers? (Sokal, 2006).
Conclusions
Of course RCTs are not the only way to get knowledge. Often they have not been done, and sometimes it is hard to imagine how they could be done (though not nearly as often as some people would like to say).
It is true that RCTs tell you only about an average effect in a large population. But the same is true of observational epidemiology. That limitation is nothing to do with randomisation, it is a result of the crude and inadequate way in which diseases are classified (as discussed above). It is also true that randomisation doesn’t guarantee lack of bias in an individual case, but only in the long run. But it is the best that can be done. The fact remains that randomization is the only way to be sure of causality, and making mistakes about causality can harm patients, as it did in the case of HRT.
Raymond Tallis (1999), in his review of Sokal & Bricmont, summed it up nicely
“Academics intending to continue as postmodern theorists in the interdisciplinary humanities after S & B should first read Intellectual Impostures and ask themselves whether adding to the quantity of confusion and untruth in the world is a good use of the gift of life or an ethical way to earn a living. After S & B, they may feel less comfortable with the glamorous life that can be forged in the wake of the founding charlatans of postmodern Theory. Alternatively, they might follow my friend Roger into estate agency — though they should check out in advance that they are up to the moral rigours of such a profession.”
The conclusions that I have drawn were obvious to people in the business a half a century ago. (Doll & Peto, 1980) said
“If we are to recognize those important yet moderate real advances in therapy which can save thousands of lives, then we need more large randomised trials than at present, not fewer. Until we have them treatment of future patients will continue to be determined by unreliable evidence.”
The towering figures are R.A. Fisher, and his followers who developed the ideas of randomisation and maximum likelihood estimation. In the medical area, Bradford Hill, Archie Cochrane, Iain Chalmers had the important ideas worked out a long time ago.
In contrast, philosophers like Worral, Cartwright, Holmes, Barry, Loughlin and Polychronis seem to me to make no contribution to the accumulation of useful knowledge, and in some cases to hinder it. It’s true that the harm they do is limited, but that is because they talk largely to each other. Very few working scientists are even aware of their existence. Perhaps that is just as well.
References
Cartwright N (2007). Are RCTs the Gold Standard? Biosocieties (2007), 2: 11-20
Colquhoun, D (2010) University of Buckingham does the right thing. The Faculty of Integrated Medicine has been fired. https://www.dcscience.net/?p=2881
Miles A & Loughlin M (2006). Continuing the evidence-based health care debate in 2006. The progress and price of EBM. J Eval Clin Pract 12, 385-398.
Miles A, Loughlin M, & Polychronis A (2007). Medicine and evidence: knowledge and action in clinical practice. J Eval Clin Pract 13, 481-503.
Miles A, Polychronis A, & Grey JE (2006). The evidence-based health care debate – 2006. Where are we now? J Eval Clin Pract 12, 239-247.
Murray SJ, Holmes D, Perron A, & Rail G (2007).
Deconstructing the evidence-based discourse in health sciences: truth, power and fascis. Int J Evid Based Healthc 2006; : 4, 180–186.
Sokal AD (1996). Transgressing the Boundaries: Towards a Transformative Hermeneutics of Quantum Gravity. Social Text 46/47, Science Wars, 217-252.
Sokal AD (2006). Pseudoscience and Postmodernism: Antagonists or Fellow-Travelers? In Archaeological Fantasies, ed. Fagan GG, Routledge,an imprint of Taylor & Francis Books Ltd.
Sokal AD & Bricmont J (1998). Intellectual Impostures, New edition, 2003, Economist Books ed. Profile Books.
Tallis R. (1999) Sokal and Bricmont: Is this the beginning of the end of the dark ages in the humanities?
Worrall J. (2004) Why There’s No Cause to Randomize. Causality: Metaphysics and Methods.Technical Report 24/04 . 2004.
Worrall J (2010). Evidence: philosophy of science meets medicine. J Eval Clin Pract 16, 356-362.
Follow-up
Iain Chalmers has drawn my attention to a some really interesting papers in the James Lind Library
An account of early trials is given by Chalmers I, Dukan E, Podolsky S, Davey Smith G (2011). The adoption of unbiased treatment allocation schedules in clinical trials during the 19th and early 20th centuries. Fisher was not the first person to propose randomised trials, but he is the person who put it on a sound mathematical basis.
Another fascinating paper is Chalmers I (2010). Why the 1948 MRC trial of streptomycin used treatment allocation based on random numbers.
The distinguished statistician, David Cox contributed, Cox DR (2009). Randomization for concealment.
Incidentally, if anyone still thinks there are ethical objections to random allocation, they should read the account of retrolental fibroplasia outbreak in the 1950s, Silverman WA (2003). Personal reflections on lessons learned from randomized trials involving newborn infants, 1951 to 1967.
Chalmers also pointed out that Antony Eagle of Exeter College Oxford had written about Goldacre’s epistemology. He describes himself as a “formal epistemologist”. I fear that his criticisms seem to me to be carping and trivial. Once again, a philosopher has failed to make a contribution to the progress of knowledge.