George Williams, the revered evolutionary biologist, describes the natural world as “grossly immoral.” Having no foresight or compassion, natural selection “can honestly be described as a process for maximizing short-sighted selfishness.” On top of all the miseries inflicted by predators and parasites, the members of a species show no pity to their own kind. Infanticide, siblicide, and rape can be observed in many kinds of animals; infidelity is common even in so-called pair-bonded species; cannibalism can be expected in all species that are not strict vegetarians; death from fighting is more common in most animal species than it is in the most violent American cities. Commenting on how biologists used to describe the killing of starving deer by mountain lions as an act of mercy, Williams wrote: “The simple facts are that both predation and starvation are painful prospects for deer, and that the lion's lot is no more enviable. Perhaps biology would have been able to mature more rapidly in a culture not dominated by Judeo-Christian theology and the Romantic tradition. It might have been well served by the First Holy Truth from [Buddha's] Sermon at Benares: “Birth is painful, old age is painful, sickness is painful, death is painful...”” As soon as we recognize that there is nothing morally commendable about the products of evolution, we can describe human psychology honestly, without the fear that identifying a “natural” trait is the same as condoning it. As Katharine Hepburn says to Humphrey Bogart in The African Queen, “Nature, Mr. Allnut, is what we are put in this world to rise above.
The universality of reason is a momentous realization, because it defines a place for morality. If I appeal to you do do something that affects me—to get off my foot, or not to stab me for the fun of it, or to save my child from drowning—then I can't do it in a way that privileges my interests of yours if I want you to take me seriously (say, by retaining my right to stand on your foot, or to stab you, or to let your children drown). I have to state my case in a way that would force me to treat you in kind. I can't act as if my interests are special just because I'm me and you're not, any more than I can persuade you that the spot I am standing on is a special place in the universe just because I happen to be standing on it.You and I ought to reach this moral understanding not just so we can have a logically consistent conversation but because mutual unselfishness is the only way we can simultaneously pursue our interests. You and I are both better off if we share our surpluses, rescue each other's children when they get into trouble, and refrain from knifing each other than we would be if we hoarded our surpluses while they rotted, let each other's children drown, and feuded incessantly. Granted, I might be a bit better off if I acted selfishly at your expense and you played the sucker, but the same is true for you with me, so if each of us tried for these advantages, we'd both end up worse off. Any neutral observer, and you and I if we could talk it over rationally, would have to conclude that the state we should aim for is the one where we both are unselfish.Morality, then, is not a set of arbitrary regulations dictated by a vengeful deity and written down in a book; nor is it the custom of a particular culture or tribe. It is a consequence of the interchangeability of perspectives and the opportunity the world provides for positive-sum games.