Answering this question, I recalled a somewhat rare construction used to express that an action is characteristic of someone. Pekkanen's Ars Grammatica (§77.1) gives two examples:
- Cuiusvis hominis est errare, nullius nisi insipientis est in errore perseverare.
- Adulescentis est maiores natu revereri.1
I tried looking this up in online Latin grammars to provide a reference, but I failed to find anything. Can someone find an online Latin grammar that discusses this use of genitive and infinitive?
I am not aware of a specific name for this, so it is hard to search. Pekkanen lists it as a subclass of genetivus possessivus, but such classification is a somewhat arbitrary choice.
1 If you are puzzled by the word natu, see this follow-up question.