Rationality leads to better choices in our lives and is the ultimate driver of moral progress claimed famous author and cognitive psychologist Steven Pinker. Yet many, including groundbreaking advertising executive and public intellectual Rory Sutherland, disagree. Sutherland was interviewed by the IAI to discuss his views on the failures of rationality, science, and the need to embrace irrationality and magic in our decision making.

You had an exchange a couple of years ago about the topic of rationality with Steven Pinker. Pinker wrote a book, ‘Rationality’, arguing that we need more rationality, and that its adoption would lead to better outcomes. You took issue with some of the conclusions that he reached. Why?

I think we have all been indoctrinated in some ways by high school science, in particular the hard sciences, to believe that there's an absolutely perfect correlation between the quality of reasoning that goes into a decision and the quality of outcome. I think that's simply an unsafe assumption for all kinds of reasons. It's a perfectly safe assumption in GCSE maths or physics when the opposite of a right idea is wrong. But in major questions, the opposite of a good idea may be another good idea. Furthermore, rationality probably didn’t evolve to drive human decision making. If you think about it, every other animal on the planet managed to survive and reproduce perfectly satisfactorily without a major faculty of reason. They did it simply on instinct.