Trade has played a vital role in the social evolution of humankind. It allowed people to specialise, which raises both skill levels and efficiency. It brought people from different lands together, co-operating rather than competing over resources.

Instead of showing strangers kindness and giving them the benefit of the doubt, we increasingly show them only fear, and that is bad for us and them.

I don't feel proprietorial about the problems of philosophy. History has taught us that many philosophical issues can grow up, leave home and live elsewhere.

No one who has understood even a fraction of what science has told us about the universe can fail to be in awe of both the cosmos and of science.

Perhaps the biggest myth about cynicism is that it deepens with age. I think what really happens is that experience painfully rips away layers of scales from our eyes, and so we do indeed become more cynical about many of the things we naively accepted when younger.

If we find it hard to believe that winning millions might not be so lucky after all, we just don't have a good enough imagination. If I fantasise about winning the lottery, it doesn't take long before all sorts of worrisome potential consequences occur to me.

Philosophy is at its most engaged when it is impure. What is being recovered from the Ancient Greek model is not some lost idea of philosophy's pure essence, but the idea that philosophy is mixed up with everything else.