"What an exhilarating but preposterous challenge: to select 20 outstanding non-fiction books from a lifetime of reading, teaching, reviewing and thinking about great literature. I can only emphasise that this is a personal choice. Everyone's list would – and should – be different. These are simply texts that in some sense I have lived through, that have changed the way I think about the world and opened up the bigger questions that confront us all as human beings. There are no formulas or rules that unite them: wisdom comes in all shapes and sizes, and all it ought to do is shake us up a bit – so don't look here for conventional moral lessons. My attempt to provide some sort of balance across time and space has meant that many a profoundly influential writer – Freud, Kinsey, Hayek, Rousseau, Thoreau, Goethe, Marx, Machiavelli, Keynes – didn't make the final cut. Books about war will be dealt with in a separate list; I hope Anne Frank's diary can find a place there." - telegraph.co.uk