Warm, sensitive, creative, outgoing, cheeky, creepy. Scan any personal ads page and it's clear that to get a life you need a personality first. It is also a notion with a long and often bizarre history: in early Greece and medieval Europe, it was thought to depend on the balance of bile in the body. "On Personality" is a thoughtful and stimulating look under the skin of this widely-used but little understood phenomenon. Peter Goldie points out that we rely on personality to do a lot of work: describe, judge, understand, explain and predict others as well as ourselves. Is it really up to this task? If personality is about "character, " is it a relic of a bygone Victorian age? If personality is so reliable, how can a virtue in one person be a vice in another? Drawing on a great range of philosophers, novelists and films, from Aristotle, Hume, Kant and Nietzsche to Joseph Conrad, "Middlemarch, " "War and Peace" and "Bridget Jones' Diary, " Peter Goldie also discusses some famous psychology experiments. If personality is a reliable guide to predicting what people will do, he reflects on why people often surprise us and asks whether personality is simply down to chance and circumstance.