My father died last summer – hence the big gap in posts while I catch up with everything else. There’s lots of things I could say about him – his love of games and puzzles for example. But here I just want to explain one thing: he taught me my first mathematics at the age of nine or ten, some trigonometry and algebra. I can remember finding mathematics at school easy and I am sure that what he taught me helped greatly. It wasn’t so much knowing the trigonometry and algebra that was so helpful, more that I understood from him how to go about doing mathematics. That seems to me to be a very important part of teaching.