The optimist underestimates how difficult it is to achieve real change, believing that anything is possible and it's possible now. Only by confronting head-on the reality that all progress is going to be obstructed by vested interests and corrupted by human venality can we create realistic programmes that actually have a chance of success.

Being virtuous is wonderful thing, but feeling virtuous is a shortcut to vice.

Whatever the truth is about the extent to which truth is respected in the future, it is going to depend partly on what we do. More important than making predictions is doing things which help bring about this respect.

Society needs both justice and compassion, a head and a heart, if it is to be civilised.

Yesterday's news feeds our fear that our neighbours are more likely than not to be bad eggs: benefit fraudsters, bogus asylum seekers, paedophiles or jihadist terrorists.

Once Steve Fuller said that there is this idea that your responsibility as an intellectual is just to speak the truth as you see it. But actually, you should be more appreciative of what needs to be said. I don't think that's ever an excuse to say something you don't believe is true - but sometimes the emphasis has to be different. Well, if I'm talking to an audience of hardline atheists, I'll be trying to unsettle them a bit more, whereas, if I'm speaking to an audience of believers, I'll be giving them more of the pros of atheism. It's about having a sensitivity to context.

Trying to keep up with health advice can feel like surfing the Net for weather forecasts: what you find is always changing, often contradictory and rarely encouraging.