Wednesday, June 10, 2020

Stove On Inclusive Fitness

People easily think that claiming a cause explains something is denying it exists. Talk to someone in the street, or an average physicist for that matter, about some secondary quality such as color. Are they saying that some cause explains why things have the colors they have, or denying that things have any color?

Perhaps the inclusive fitness theory is not about what causes kin altruism, and maybe it's not a denial of kin altruism. Perhaps sometimes it's claiming a cause of kin altruism and sometimes it's a denial that kin altruism exists. Shared genes cause kin altruism and are the reality underlying the illusory appearance that there is such a thing as kin altruism. Some scientists believe this about color.

But the inclusive fitness theory explains why the literature of inclusive fitness contains contradictory estimates of how much altruism there is in the world.

It might be claimed that this is a misunderstanding of the inclusive fitness theory, and that kin altruism is real at the level of individual organisms. Think of parental altruism in humans, of sibling altruism in hymenopteran workers, and so on. Hamilton said the selfishness of genes causes kin altruism.

No suggestion of universal selfishness here. And, taking the inclusive fitness theorist at their word, we adopted his causal explanation of kin altruism in section iii above. It led us to a number of surprising results. For example, that there is twice as much sibling altruism between bacterial as between human sisters; that sibling altruism in our species is as common and strong as parental altruism; that every parent bird will sacrifice its own life in order to save three of its nestlings; and so on. And the combined result of all these discoveries was, that there is in fact far more kin altruism in the world than anyone had ever supposed before the inclusive fitness theory came along. In fact it turned out that animal life is saturated with kin altruism: drips the stuff at every pore.

And yet, in the literature of the inclusive fitness theory, what do we actually find? 166 Why, more often than not, the universality of 'dog eat dog', of 'dirty tricks', of the self-interested manipulation of offspring by their parents, of parents by their offspring, of siblings by each other, of strangers by everyone; of apparent altruism revealed as hypocrisy, (even, no doubt, in those luckless hymenopteran workers who had previously been portrayed as paragons of kin altruism). There is no pretence, in this part of the literature, of admitting the reality of kin altruism and confining selfishness to the gene level. On the contrary, it is the Hobbesian war of all against all, openly installed (not for the first time) as the last word in Darwinian biology. There is not, it turns out, one atom of kin altruism in the world: it is an illusion.

In any discussion of the inclusive fitness theory with an adherent of it, the same extraordinary phenomenon of 'Janus faces' will be met with. On one face of thc theory, arising out of the idea that kin altruism is caused by shared genes, there is an extravagant exaggeration of the amount of kin altruism that exists; on the other, there is the idea that kin altruism is an illusion, the underlying reality of which is shared selfish genes. Any discussion of altruism with an inclusive fitness theorist is, in fact, exactly like dealing with a pair of air balloons connected by a tube, one balloon being the belief that kin altruism is an illusion, the other being the belief that kin altruism is cansed by shared genes. If a critic puts pressure on the illusion balloon - perhaps by ridiculing the selfish theory of human nature - air is forced into the causal balloon. There is then an increased production of earnest causal explanations, of why we love our children, wfty hymenopteran workers look after their sisters, etc., etc. Then, if the critic puts pressure on the causal balloon - perhaps about the weakness of sibling altruism compared with parental, or the absence of sibling altruism in bacteria - then the illusion balloon is forced to expand. There will now be an increased production of cynical scurrilities about parents manipulating their babies for their own advantage, and vice versa, and in general, about the Hobbesian bad times that are had by all.

In this way critical pressure, applied to the theory of inclusive fitness at one point, can always be easily absorbed at another point, and the theory as a whole is never endangered. A defender of the theory does need, it is true, a certain mental agility: an ability to make sudden and extreme'gestalt switches', (as the best authors in the philosophy of science now say), from a pichre in which animal life is swimming in kin altruism, to one in which there is no kin altruism at all. But this ability, it has turned out, is by no means uncommon; and it is the only one which a defender of the inclusive fitness theory needs. Given that, his theory is stable rmder any criticism whatever.

My hypothesis - that inclusive fitness theorists are just confused about kin altruism, and oscillate between denying it and trying to explain it - has at least the merit, therefore, of explaining something otherwise improbable: the Janus faced character of their theory. But it also has in its favour a historical fact which I point out in Essay VI: rhat selfish theorists have always oscillated between a version of their theory which is shocking but not true, and a version which is perhaps true, but certainly not shocking, or even interesting.

[page 168] When an inclusive fitness theorist tells us that kin altruism does not exist, then that is shocking all right; but it is not true. when, on the other hand, he only tells us that kin altruism is caused by shared genes, then that happens not io be true, (as we saw in section iii), but even if it were true, it would not be shocking, or eyen interesting. If kin altruism ls caused by shared genes, that is well - it exists, anyway; if it is caused by something entirely different, well again. who doubts that it is caused by something? Nor can its cause be of a very rare or elevated character, in view of the extreme conmonness of kin altruism which, (at least in its parental form), extends even to such low spirituality types as alligators. The fact that kin altruism has a cause does not prevent it from being sometimes an admirable thing, cither. By that overly severe rule, there would be nothing to admire anywhere; not cven in, say, The Selfish Gene [book], which presumably has its causes like everything else in nature.

--David Stove, Darwinian Fairytales, pages 166-168.

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