I have been meaning for some time to set down my reasons for thinking that evolutionary psychology is only questionably a discipline. At least seven reasons occur to me (actually more, but these seven are top of mind):
1. There is no actual “subject” for the research. The subject of evolutionary psychology is a hypothetical construct: “early humans,” whose genes are thought to survive in modern humans and govern our behaviour. But these early humans have not existed for at least a hundred thousand years, so their behaviour can never be directly tested. It reminds me of the problem with the biology of extraterrestrial life forms – a discipline without a subject, as Simpson noted.
2. It is pure conjecture that given common types of behaviour are somehow inherited from early humans. In most cases, a simpler, more obvious explanation is readily available. For example, an evolutionary psychologist might argue that a woman doesn’t want her man to cheat because he might produce children with another woman and thus prevent her from passing on her selfish genes. But such an explanation defies Occam’s Razor (the simplest explanation is best). Obviously, she does not want her man to cheat because she does not want attention directed at another woman that could be going to her. Whether she is – or ever will be – infanticipating is irrelevant to her and – for that matter – irrelevant to her genes. She would feel the same way if she were 17 or 70. It is hard to imagine a state of human or proto-human life in which things could have been any different.
3. We have no way of knowing precisely what behaviours – beyond the most obvious, like avoidance of suicide and infanticide – helped early humans survive and procreate. One hundred thousand years ago, was it better to be faithful? Unfaithful? Pious? Impious? Daring? Sneaky? Jealous? Prone to violence? Placid? Well, it takes no very great experience of life to see that almost any type of non-suicidal behaviour may be rewarded under a given circumstance. The critical thing that we do not know is exactly how those specific humans who became our ancestors behaved. We also do not know if their behaviour could be passed it on to us by some sort of irrevocable gene – but it seems unlikely.
4. The actual number of common human ancestors is widely regarded as small. This is a much bigger problem than some sources are willing to admit. If the actual number of human ancestors had been large – the majority of humans who lived 100 000 years ago, let us say – we might make do with a sort of “group psychology.” Sloppy but at least barely possible. That is, we could say that the behaviour of the majority probably helped survival and that it is tracked in the similar behaviour of the majority today. But the actual number is quite small in comparison with the numbers who have ever lived. Our chances of determining how those few individuals came to be ancestors is accordingly reduced.
5. Lack of an obvious mechanism. If there were truly a gene for infidelity, for example, maybe Francis Collins or Craig Venter could find it – and people contemplating marriage might wisely insist that prospective spouses get tested. Then the media would be full of angst about all that. But all we hear is vague talk about behaviour that supposedly spread selfish genes among early humans, and allegedly governs our behaviour today. If there was anything in it, someone would have a patent right now, and governments would be bringing in legislation against it.
6. Oh, and don’t get me started on the meme nonsense. Undeterred by the lack of genetic evidence, the evo psychos began to claim that there was an abstract equivalent of the gene, the “meme” that governs thoughts. No one has ever detected one, and the word meme has simply become a way of referring to ideas that one feels superior to. We used to call them “intellectual fads”, but I admit that “meme” is shorter’.
7. Some human behaviour does seem to stem from specific inherited tendencies, but – significantly – that isn’t the sort of behaviour that tends to interest the evolutionary psychologist. Humans are predominantly right-handed, for example, rather than left-handed. It would be interesting to know why. I am told that chimpanzees, by contrast, show a preference for one hand, but it could be either one. One outcome of the predominant human inheritance of right-handedness is that “right” vs. “left” inevitably acquires a cultural value (essentially good vs. bad). In some cultures, you just cannot be left-handed, period – even if attempts to make you right-handed result in a speech impediment (because they may interfere with speech areas of the brain).
Another probable genetic endowment is the human preference for warm climates. It is common to hear people freak out about overpopulation. As a Canadian, I have long advocated a simple answer: Move the excess human population to northern Canada. We need more people. The only problem is, they won’t GO! There’s lots of space up there, but few people seem to want it. If you want to know why, check a hardiness zone map. The fact is, humans would rather be poor and crowded in a warm place than huddled over a heater with two hundred kilometres of frigid, empty space around them – and ten thousand bucks in a bank somewhere. Of course, the fact that we don’t have a lot of body hair or fat under our skin or antifreeze in our joints probably has something to do with our prejudice against frigid climates …
In other words, there are verifiable human tendencies that can plausibly be traced to our genetic endowments. The problem is that these tendencies tell you only that our obvious, demonstrable genetic endowments have far-reaching consequences. They don’t particularly support theories that show that humans are just animals with big brains, which is the real agenda of Darwinism. So the evolutionary psychologist is generally not interested in this stuff, however significant it might be in interpreting human culture and history. No, the big prize is the nebulous stuff, like why Ned Flanders got religion and Homer Simpson didn’t – postulated as caused by a selfish gene, inherited because it “would have helped an early human ancestor find a mate.” Or maybe it didn’t … maybe it was a rogue gene that just happened to survive! Yeah really.
Recently, I haven’t been blogging much because I am in the home stretch of Mario Beauregard and Denyse O’Leary, The Spiritual Brain (Harper, March 2007), which will dispose of evo psycho in some detail – as a side issue. We are after bigger and more interesting fish.
But I have not given up blogging. I am slowly working my way through the inbox … So, for some of my comments on recent events in the intelligent design controversy, go here, here, and here.