When backed into a corner, most hard-line utilitarians concede that the standard counter-examples seem extremely persuasive.  They know they’re supposed to think that pushing one fat man in front of a trolley to save five skinny kids is morally obligatory.  But the opposite moral intuition in their heads refuses to shut up.

Why can’t even utilitarians fully embrace their own theory?  The smart utilitarian answer blames evolution.  Scott Sumner:

Other “counterexamples” take advantage of illogical moral intuitions
that have evolved for Darwinian reasons, like discomfort at pushing a
fat man in front of a trolley car to prevent even more deaths.

I’m the first to concede that human beings haven’t evolved to be perfect truth-seekers.  But what’s the epistemically sound response to the specter of evolved bias?  “Be agnostic about every belief that, regardless of its truth, helps your genes,” is tempting.  But it’s also absurd. 

How so?  Virtually every moral philosophy – including utilitarianism – agrees that a happy life is better than (a) death, or (b) suffering.  But evolutionary heavily favors these value judgments!

If you aren’t convinced that life is better than death, or that happiness is better than suffering, you swiftly drop out of the gene pool.  And since human beings are social animals, we’re evolved to value the lives and happiness of the people around us as well as our own.  Should we therefore dismiss our anti-death, anti-suffering views as “illogical moral intuitions
that have evolved for Darwinian reasons”?

The moral nihilist, who bites even more bullets than the utilitarian, can enthusiastically agree.  Everyone else, however, has to say, “Yes, it’s logically possible that we’re evolved to falsely believe that life and happiness are better than death and suffering.  But after calm reflection on this potential bias, I remain convinced of the merits of life and happiness.”  And if you use this approach for life and happiness, why not try it for murdering innocent fat guys?

None of this means that moral intuition is infallible.  Serious intuitionists question their moral intuitions all the time.  The reasonable response to evolved biases, though, is to calmly review suspect beliefs – not dismiss the obvious.