I defended my PhD on 15 May 2003, in the Senate Chamber. You sit facing the opposition, but also facing Scaliger. In the corner of your left eye, you catch sight of Bolland. The audience is behind you. Your supervisor warns you not to make any jokes, 'because it's a serious occasion, and you never know how a joke will land.' Then the first opponent brings up a passage I had recently discussed with students, during which I had made a joke they enjoyed. So I repeat that well-tested joke. Laughter erupts behind me. All the tension disappears. In Leiden, you defend your PhD in the Senate Chamber.
