John the science technician and I were finishing our coffee at morning break time. He looked over to a pile of children’s books left on a low table by a travelling saleswoman. “There’s a religious version of that one,” he said, “called St Thomas Aquinas the Tank Engine.” I laughed until I could barely see, though in my mind I was picturing a train with a pious little face and a bishop’s hat for a steam dome. The moment has become my gold standard. If I think about it and don’t start smiling, I know that I am seriously down in the dumps.

A number of you are probably thinking “Eh?”. For humour, more than anything else, surely reveals that we don’t all think the same way. Great minds don’t think alike, and neither do non-great minds. Working in the lab a few months ago, I caught snatches of a radio interview with Daniel Tammet, who has Savant Syndrome, a rare form of Asperger’s. He can learn a new language in a week and was able to give the value of pi, from memory, to over 22,000 decimal places. I bought his autobiography, Born on a Blue Day. The title is misleading. This is not a sad book, despite Daniel Tammet finding school very difficult. He perceives days of the week as having different colours. Numbers too have colours and shapes, and it is this synaesthesia that he reckons gives him his astounding mathematical and linguistic abilities.

I once took over a rather unruly class and, to my shame, neglected to look over the list issued to teachers detailing health and other issues of the year group before having them for the first time. A boy appeared at my door as the others filed in. “Am I supposed to be here?” he asked. I snapped something unhelpful and turned my attention to someone who was being an eejit elsewhere.

I failed to notice that the questioner had vanished; indeed, I barely remembered the incident until a support lady came to talk to me. The boy had Asperger’s. He found changes in his routine hard to cope with.

I have heard that parents with children on the autistic spectrum hate to be asked “does he have any special talents?”, because it does not follow. However, this chap, helped by pupil support teachers to settle in my class, proved to have just the sort of analytical streak to his thinking that suits physics. I was able to tell him how much I enjoyed checking his work. By the time he sat Higher, I had left, but I heard that he did very well. That made me smile, but not in the way that St Thomas Aquinas the Tank Engine does.

Gregor Steele also associates colours with days. Fridays are yellow.