You can reasonably make the intellectual journey from thinking it's permissible to eat shrimp to thinking it's not permissible, or vice versa, whereas our slavery journey was uni-directional. We are as certain we are not going back to that old kind of slavery as we are that we aren't going back to the geocentric universe.

In the academic setting, you take (typically) lonely, interesting middle-aged men and beautiful, intelligent young women, and everybody's motivations for display and conquest are engaged to the max. Sublimated, this can be a powerful force for the good - Plato had a lot to say about that - but acted upon it can bring evils without end.

I think we do have a better understanding now of how moral thought and discourse function.

We are now returning to the 18th century empirical approach with the new interest in the evolutionary basis of ethics, with 'experimental' moral philosophy and moral psychology. As a result, we understand better why moral formulas are experienced as ineluctable commands, even if there is no commander and even if the notion of an inescapable obligation is just superstition. So moral philosophy has made huge progress.

I had the idea that there were secret laws of the universe that could explain the baffling human reality around me, and that philosophers maybe had the key to them.

People formerly seemed unable to evaluate a woman's c.v. or to accept a range of personal and communicative styles from the exuberant and confident to the sober and pedantic. It's much better than it was, and a number of male philosophers have been extraordinarily helpful in detecting and criticising everyday sexism in the profession.

The Epicureans denied that the gods had created the world and also denied that they played any role in it.