I can say that we aren't known for our sense of fun. [Being known as the killjoy Time Lord is like being known as the angry Dalek by other Daleks.]

But by the time I was fifty I stopped worrying about what the others thought of me. [And started working under the assumption that sense he was unliked anyway, he might as well *earn* that dislike. But it's not entirely true that he stopped worrying about what people thought of him. He stopped concerning himself with being liked, true, but he still, and always, craves respect.]