When we look back at the beliefs and practices of our ancestors, we are often shocked at what they found morally acceptable: the public torture of criminals, the trading of slaves, and the subjugation of women.

The history of moral change—change in what is, and is not, considered morally acceptable—encourages greater skepticism about our current moral beliefs and practices. We might like to think we have arrived at a state of great moral enlightenment, but there is reason to believe that further moral revolutions await. Our great-great-grandchildren may well look back at us in the same way that we look back at our great-great-grandparents: with a mixture of shock and disappointment. Could they really have believed and done that?

+INFO: Wired

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