Esprit d'escalier

[pozorvlak]

I was at the Heriot-Watt semigroup day on Friday (at which I was one of a surprising number of category theorists).

It was only after I'd got there that I realised I should have been wearing my No2ID T-shirt...

Comments

[pozorvlak.livejournal.com]

I was wondering how long it would take someone to ask. Semigroups are mathematical structures like monoids, but which don't necessarily have identity elements.

I didn't say it was a good joke...