IDU: Why is rationality so hard for some people?

Rationality matters. It leads to better choices in our lives and in the public sphere, and is the ultimate driver of social justice and moral progress. So are humans innately rational or irrational? And why is it difficult for some people to be rational? Johnstone Family Professor of Psychology at Harvard University Steven Pinker joins William Shatner on this week's episode of 'I Don't Understand' to discuss how do we embrace rationality and why is it sometimes really hard to do.