The historical reality is much more complex and nuanced than the sketch I’m about to describe, I’m sure, but I hope it’s useful anyway.
Imagine a population of hominids, some of whom will have descendents who’s lineage, if followed, will eventually lead us to humans.
The hominids have figured out that they can lead better lives and get the things they want more effectively if they cooperate. But the temptation to cheat and steal is ever present.
Now imagine that because of genetic accident, or social innovation, or a combination of both, some of these hominids come to believe that certain acts have a quality that we can call 'must not be done-ness’. They come to believe very strongly that there’s an absolute injunction against doing certain things, that these things are 'just wrong’, and that their wrongness is a non-negotiable part of the universe. For these individuals, stealing is wrong and remains wrong even if you can get away with it and regardless of what your goals or preferences are.
If it turned out that this strange new belief benefited the individuals who held it, making it more likely that they’d have viable offspring, then it would increase the host animals’ changes of passing on their DNA to future generations. Eventually, after a number of generations, almost all members of the population would hold similar beliefs if the adaptive value of these new beliefs was great enough.
Perhaps current the near-universal belief in moral facts among humans is the consequence of such a process. The belief in moral facts, and the intensity of that belief, may result from a subtle combination of genetic and environmental factors that have been benefiting our ancestors since they first emerged.
None of this would mean that the belief that stealing is wrong is true in any absolute sense, but merely that historically it has been beneficial for human ancestors to believe that this is true.
On this view, no one needed to teach humans that stealing was wrong in the same way that no one needed to teach birds to fly.
Richard Joyce’s book The Evolution of Morality talks more about these ideas.
Posted: August 7th 2011
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