Barack Obama: “If there's something you know you have to do, even if it's difficult or unpleasant, you might as well just go ahead and…”

And I will fight for that, even if I don’t always think it’s going to win.

A drift towards extremism was "not inevitable

When we choose, when we make that decision, I do believe – and there is evidence for this – that the world gets incrementally better, and that is a worthy goal and it’s worth fighting for.

If I had a blame pie for why politics is so polarised and why we're seeing a rise of populism in many places, it's because of that information that is going into our brains every day.