The Curious Incident of the Dog in the Night-Time
The rule for working out prime numbers is really simple, but no one has ever worked out a simple formula for telling you whether a very big number is a prime number or what the next one will be. If a number is really, really big, it can take a computer years to work out whether it is a prime number. (19.6)
I was also wearing my watch and they wanted me to leave this at the desk as well but I said that I needed to keep my watch on because I needed to know exactly what time it was. And when they tried to take it off me I screamed, so they let me keep it on. (23.4)
He said that I was clearly a very logical person, so he was surprised that I should think like this because it wasn't very logical.
I said that I liked things to be in a nice order. And one way of things being in a nice order was to be logical. Especially if those things were numbers or an argument. But there were other ways of putting things in a nice order. And that was why I had Good Days and Black Days. [...]
I said that when Father got up in the morning he always put his trousers on before he put his socks on and it wasn't logical but he always did it that way, because he liked things in a nice order, too. Also whenever he went upstairs he went up two at a time always starting with his right foot. (47.2-4)