In this exclusive interview with the Institute of Art and Ideas, in the run up to HowTheLightGetsIn London 2022, groundbreaking ethicist and philosopher Peter Singer clarifies his stance on moral objectivity, the role of intuitions in ethics and where we draw the line for holding people responsible for inaction.

In various interviews you have stated that you have moved from moral anti-realism - the view that there are no objective moral values - to moral realism - the view that there are objective moral truths. What initiated this shift?

For many years, after studying at Oxford, I considered myself a universal prescriptivist – the position taken by R.M. Hare, who was my supervisor for much of my time at Oxford. Hare always insisted that, even for prescriptivists, reason had an important role to play in reaching moral judgment. But the problem was for Hare, reason only had this role because of what he argued was the logic of moral concepts.  So if you don’t use moral language – in other words, become an amoralist – it seems that you have no reason, other than self-interest, to avoid, say, gratuitously punching someone in the face.