Over time, the welfare state has become dysfunctional in a surprising way. But in a way it became a victim of its own success: It became so successful at prolonging life, that it becomes financially unsustainable, unless you make major changes to things like retirement ages.

Civilisation is partly about restraining the male of the species from engaging in the violence of the hunter-gatherer period. But it doesn't take an awful lot to unleash it.

The whole point about historians is that we are really communing with the dead. It's very restful - because you read. There's some sociopathic problem that makes me prefer it to human interaction.

I think the rise of quantitative econometrics and a highly mathematical approach to risk management was the obverse of a decline in interest in financial history.

As a financial historian, I was quite isolated in Oxford - British historians are supposed to write about kings - so the quality of intellectual life in my field is much higher at Harvard. The students work harder there.