Humanity is flourishing and the Enlightenment has worked, declares Steven Pinker. The Harvard psychologist has looked across health, prosperity, safety, peace and happiness, and sees signs that all are improving. He tells Andrew Marr how Enlightenment attitudes to reason and science have made this the best age in which to live. But Enlightenment values are under attack and Pinker calls for their vigorous defence.

Dutch philosopher Rob Riemen also sees humanism under threat from fascism, with its politics of resentment and hatred of the life of the mind. But can reason, beauty and justice combat this threat?

The neuroscientist Tali Sharot thinks reason and fear are not enough to make us change our minds. Only by understanding how the brain functions can we perfect the art of persuasion.

Producer: Hannah Sander.