  The strained precision of clock time was alien to him, so he was usually late for his own lectures (or anyone else’s for that matter—he was very egalitarian about it). But he almost always turned up eventually, thinning hair blown vertical by his dash on his bike when he remembered the time. He would pull cycle clips off his trousers and plonk an ancient shopping bag on the desk in front of him. Out of this bag would come … a cabbage, a bunch of carrots, a loaf of bread, a bottle of milk … until, always at the bottom, he would find the book he was looking for. Back into the bag went the rest of the goodies, then he would look up at us, apologise for being late if he was more than usually so, and ask: ‘Now where were we last time?’ Someone in the front row would consult her or his notes—Arthur couldn’t as he never had any—and would say ‘You were just dealing with such and such’. ‘Ah yes, thank you’ Arthur would respond, and forthwith launch into an extempore exposition which followed on perfectly from the previous session and was beautifully structured and clear even though he was just thinking along with us. And of course we could stop him and ask for clarification or elaboration at any time, without in the slightest affecting the overall structure and direction of his thoughts.