I find this amusing, from "On being a joyful curmudgeon", Fr Dwight Longenecker:
It is a widely agreed precept that a many of a certain age, if he is sane, ought to be a curmudgeon.
Definition of curmudgeon
1: a crusty, ill-tempered, and usually old man
Why should he be a curmudgeon? Because by the time he has reached a certain age he should also have attained a certain level of wisdom and knowledge which will cause him to understand with increasing clarity how stupid, vain, shallow, lustful, greedy and idiotic most of this world and the people in it actually are.