A week ago I heard the very sad news that Jan Saxl has died. Jan was my PhD supervisor at Cambridge – I spent three and a half years working under his guidance. The opportunity to work with Jan was one of the great privileges of my mathematical life, and I owe him a great debt for helping me through the difficult process of researching and writing a doctoral thesis.

As well as being a fine mathematician, Jan was a warm and witty man. Now I have PhD students of my own I know that it is not always easy to know what the right thing to do is when it comes to supervision – looking back I appreciate Jan’s gentle direction all the more.

I feel very sad knowing that Jan is no longer with us. My thoughts are with his wife, Ruth, and the rest of her family.