How Your Brain Invents Morality
In her new book, Conscience, Patricia Churchland argues that mammals — humans, yes, but also monkeys and rodents and so on — feel moral intuitions because of how our brains developed over the course of evolution. Mothers came to feel deeply attached to their children because that helped the children (and through them, the mother’s genes) survive. This ability to feel attachment was gradually generalized to mates, kin, and friends. “Attachment begets caring,” Churchland writes, “and caring begets conscience.” Conscience, to her, is not a set of absolute moral truths, but a set of community norms that evolved because they were useful. “Tell the truth” and “keep your promises,” for example, help a social group stick together. Even today, our brains reinforce these norms by releasing pleasurable chemicals when our actions generate social approval (hello, dopamine!) and unpleasurable ones when they generate disapproval.