Some fields that claim the authority of science may be in need of an overhaul. This article is based on a presentation to the NZ Skeptics 2009 conference in Wellington, 26 September.

I have always been in two minds about scepticism. I am undoubtedly a sceptic by nature; I enjoy questioning and challenging things. It suits my temperament and I like to think adds something important to a discussion. But a true sceptic must be sceptical about scepticism too, and it’s hard to escape two weaknesses in the scepticism agenda. The first is oft noted. As the British philosopher Roger Scruton puts it, when a sceptic tells you nothing is true, they are telling you not to listen to them, so don’t.

Of course, few confessed sceptics are sceptics in this pure philosophical sense. In some things we must opt for mindless belief in order to function. Without our commitment to notions of causation for instance, or other minds, or time, or the rules of logic, we would be unable to make much headway in the world; yet none of these core principles are able to withstand the sceptic’s gaze. And so, quite sensibly, we do not look there. The typical sceptic, it seems to this outsider, is more a champion of an evidence-based form of something we might call scientism. Their mission becomes the challenging of those forms of knowledge which appear to pay scant regard to the available set of observations. The trouble here is that limited resources mean there are only so many places the sceptical gaze can shine and choices must be made. Sometimes prejudice will determine which knowledge is scrutinised and which is left alone, or worse still, laziness. It is all too easy to attack the hapless for our own amusement, while leaving the powerful unchallenged.

The second problem is one of ‘busybodyism’. I myself have little time for quackery and superstition but most of the time I find it hard to care whether others share my perspective. Yes, it is clearly wrong for those pretending to talk to the dead (or rather pretending the dead talk back) to exploit the grieving, but to those who enjoy recounting their ghost stories and snorting their arnica I tend to feel why not leave them to it. Who am I to say my life’s any richer for having forgone such flim-flammery?

It is with these caveats in mind that I turn my attention evolutionary psychology. Here is a refuge of shysters that by and large is not subject to the same level of attack endured by astrology, which is odd to me, for the methodologies are remarkably similar. I suspect it’s got something to do with the fact that it happens not in the tents of a gypsy fair but within the hallowed hallways of academia, and better still often within spitting distance of the science faculty. And to allay my second concern with scepticism, I have little trouble being a busybody in this area for the simple reason that the activities of academics are so often tax-payer funded, and given the vital role of academia in protecting and advancing knowledge it’s quite okay to hold these people to a higher standard.

So, why be sceptical about evolutionary psychology? Well, because it’s not scientific in its approach and yet attempts to hide behind the language of science, and to me that feels like an intellectual fraud. I can’t make that claim without first defining what I mean by science and given the millions of words that have been written on the slippery topic I’m clearly going to have to oversimplify.

The basics of the scientific method are well known. At heart this is a discipline based upon observation, hypothesis making, prediction and testing. The remarkable power of science to advance our knowledge stems for the ability to test the claims we are making against the data, and crucially this data is at its most powerful when it is generated by the hypothesis, rather than representing a cobbling together of the already known facts.

Before the General Theory of Relativity, nobody imagined that light would be bent by gravity. When Eratosthenes predicted the angle of the sun as measured by the shadows in a well shaft would be different at the same time of day, he was using the hypothesis of a curved earth to generate a novel prediction (and so test his hypthesis). When Fresnel’s equation predicted that light waves would produce a bright patch directly behind an obstacle he forced the French academy to rethink their acceptance of Newton’s particle theory of light. And closer to home, when David Penny and Mike Hendy working out of Massey University predicted that species relatedness would produce particular patterns in as-yet untested genetic sequences, they gave us a way of verifying the evolutionary hypothesis.

In all these cases and so many more we are awestruck by the power of science to not just explain existing facts, but also generate new ones. If you look at X under circumstances Y, I predict you will see Z, says the scientist. And what’s more, if you don’t then my theory is at least partially wrong. On the back of this method we have developed the technologies that underpin the modern world.

Evolutionary psychology, the claim that understanding our evolutionary past will help us better understand our contemporary behaviour, has none of these attributes, although at first glance it can appear to. Ostensibly the discipline seeks first to read the known data, our understanding of the evolutionary processes by which we were designed, then build its hypotheses, speculations about the behavioural tendencies of modern humans, and finally using the tools of psychology to test these hypotheses against the observations of our contemporary behaviour. Unfortunately, any resemblance to actual science is entirely coincidental. For evolutionary psychology as it is currently practised contains three crucial flaws.

The first comes from the requirement that a hypothesis, in order to be tested, must make a unique prediction. If two hypotheses both generate the same prediction, then experimentation will yield no means of deciding between them. Take the claim for instance that certain aspects of our appreciation of art are innate. Well yes, that’s a sensible enough idea, it may well be true and although difficult to test, it’s probably not impossible. Commonalities across time and culture provide clear hints that there is a genetic component at work.

However, and here’s the rub, there is nothing about evolutionary theory that gives it exclusive right to this claim of innate aesthetics. A creationist could equally well argue that God himself endowed humanity with these basic tendencies to assess and report upon the world’s beauty. Both hypotheses generate exactly the same predictions and this is a clear sign the evolutionary part of the process is not a scientific one, for in science predictions are used to choose between rival explanations.

A second huge problem is that we don’t actually know much about our evolutionary past, and so the blocks with which we build our initial hypotheses are spectacularly inadequate. Sometimes, when reading the claims of the evolutionary psychologist, it is tempting to imagine the savannah was fully equipped with CCTV cameras and Facebook. Complex stories are built about social structures, hunting and collecting rituals and mating preferences, and what emerges is a rendering of our evolutionary past that owes more to the Flintstones than any compelling archaeological evidence.

Take for example the initially persuasive claim that the difference in the reproductive potentials of men and women led to men (competing to mate with as many as possible) the aggressors, and women (attempting to raise the healthiest possible) the choosey co-operators. A cave man version of the courting practices of birds is evoked and because the language used is faux scientific, we are expected to buy the construction.

Again, it is possible that our distant ancestors arranged themselves this way but it is by no means certain. It is equally plausible that the emergence of language and complex culture changed the game completely, selecting against male aggression and for charm and social acumen. While Conan is out smiting all with an ass’s jawbone, Romeo is inside the cave getting to know his wife. We have examples from the primate world of females being the dominant aggressors and more importantly the emergence of complex language sets the human ape apart, generating unique selective pressures that we can only guess at.

The key moments in the evolution of the human mind revolved about the invention of language and so it is worth asking the evolutionary psychologist, how did language first come about, where and when, under what environmental pressures did it develop and what was it used for? Until we can answer these questions, and perhaps some day we will be able to, we do not have the basis the theory requires.

This second flaw exposes the third problem. We are not in fact using data from the past to form hypotheses about the present state of the human mind. Rather we are using our observations and testings of our current psychology to speculate about the nature of our evolutionary past. We are reversing the entire scientific process. Because we observe modern males indulging in more physical forms of aggression we guess this is innate (an heroic assumption in itself) and then cobble together an evolutionary ‘Just So’ story to give these modern prejudices the veneer of social respectability. And that is story telling. It is often diverting and frequently amusing, but only in the way that a horoscope is.

What’s actually happening is that contemporary studies of human psychology, which should be judged purely upon the contemporary data they generate, have their credibility bolstered by an appeal to a distant past that exists only in the imagination of those wishing to sell their theory.

Do men and women in general use different methods to get their bearings? A lot of experiments suggest they do. Okay. Is there a genetic basis for this? We could certainly look for one. Does a cock-and-bull story about how men roamed further in their hunting of animals while women paid close attention to the details of where particular berries would be found add anything to our knowledge of this phenomenon? Well, it adds colour and saleability I suppose, but that is a lousy criteria by which to judge scientific advancement.

How has all this happened? One can only speculate. Partly it may be the thrill that comes to academics when they cross into a new discipline. Suddenly everything is fresh and exciting again, and the new perspective gives them great energy. Partly it’s just that we all love a good story, particularly when so many of the tales in the area centre around the eternally fascinating topic of gender.

So should we be sceptical about these works of fiction parading as scholarly analysis of our past? Absolutely. We should mock them with the same gusto we mock the water diviner and the investment adviser. So come on sceptics, this is a call to arms. Out the phonies wherever you find them.

Interestingly none of this means we should give up on the field of evolutionary psychology completely, for the hypothesis does have one testable and important implication. If indeed our evolutionary past has hard-wired certain behavioural tendencies then clues of this process will still lurk in our DNA. Longitudinal studies like the groundbreaking work coming out of Dunedin are beginning to mine the potential in this approach. But the work is long and painstaking, the conclusions complex and tentative and subject to constant revision.

The picture slowly emerging is one of delicate feedback between gene and environment and the stories to be told are cautious, fragile things. Real science in other words, is potentially about changing the face of our future. That’s where the resources should be going.

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