How Humans Became Moral Beings | Science | Smithsonian
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How Humans Became Moral Beings



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First of all, how do you define altruism?


Why is altruism so difficult to explain in evolutionary terms?


What did Charles Darwin say about this “altruism paradox?”




And what did Darwin have to say about the origins of the human conscience?

What he did really was to take the conscience, set it aside as something very special and then basically say, “I throw up my hands. I can’t tell you how this could have evolved. What I can tell you is that any creature that became as intelligent and as sympathetic as humans would naturally have a conscience.”

Fast-forward a century and half—where are we now in understanding the origins of human morality and conscience?

Well, there are quite a few books on the subject. But they are almost all arguments out of evolutionary design; that is, they simply look at morality and see how it functions and how it could have been genetically useful to individuals. My book is the first to actually try to look at the natural history of moral evolution. At what time and how did developments take place which led us to become moral? In a way, this is a new field of study.

Can you tell us about the database you have created to help you draw your conclusions?

It has been argued that all of the human hunter-gatherers that live today have been so politically marginalized that they really can’t be compared with prehistoric human beings who were hunting and gathering. I think that is flat-out wrong.

Since the 1970s, we have learned that the rate of climate change was just incredible in the late Pleistocene. Therefore, there was plenty of marginalization taking place 50,000 years ago, just as there has been today. Like today, some of it surely was political, in the sense that when there would be a climate downswing, everything would be scarce and hunting bands would be fighting with each other over resources.

What I have done is to look at all of the possible hunter-gatherer societies that have been studied. I simply got rid of all of those that could have never existed in the Pleistocene—mounted hunters who have domesticated horses that they got from the Spaniards, fur trade Indians who started buying rifles and killing fur-bearing animals and some very hierarchical people who developed along the northwest coast of North America. So far, I’ve very carefully gone through about 50 of the remaining societies, looking for things that they mostly share. Then, I project the patterns of shared behavior back into the period when humans were culturally modern. Now, that only gets us back to 45,000, maybe 100,000 years ago. If you go back beyond that, then there are problems, because you are not dealing with the same brains and the same cultural capacity.

About when did humans acquire a conscience?

Getting pinned down on a date is very dangerous because every scholar is going to have something to say about that. But let me just give you some probabilities. First of all, there could be little doubt that humans had a conscience 45,000 years ago, which is the conservative date that all archaeologists agree on for our having become culturally modern. Having a conscience and morality go with being culturally modern. Now, if you want to guess at how much before that, the landmark that I see as being the most persuasive is the advent of large game hunting, which came about a quarter of a million years ago.

According to your theory, how did the human conscience evolve?



Over how long of a period did it take to evolve?

Well, Edward O. Wilson says that it takes a thousand generations for a new evolutionary feature to evolve. In humans, that would come to 25,000 years. Something as complicated as a conscience probably took longer than that. It has some bells and whistles that are total mysteries, such as blushing with shame. No one has the slightest idea how that evolved. But I would say a few thousand generations, and perhaps between 25,000 and 75,000 years.

In what ways is morality continuing to evolve?




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