In order to book me to give one of these lectures – or to speak to a title of your own invention - there are four steps:
1.Decide if you are a “Good Cause”, able to persuade me to take “expenses only” because of the warm glow I’ll get, for example. But not if you’re in Orkney or New Zealand. Or the other side of London.
2.Decide if I’ll enjoy your audience – and if so, put in a long discussion period so that I can. Then much of my reward need not be monetary. But I don’t go to events that cost me money, these days. If you’re a S-f convention, or a scientific conference, you pay all my expenses or (mostly) I don’t come.
3.If you give me only one hour in total (much more difficult to talk for 40 mins on those subjects, I have 55-ish mins planned), and/or if you’re rich and/or prestigious, start thinking £500 + expenses.
4.Ring me or e-mail and discuss dates and titles, audiences and emoluments.