Faced with the choice between changing one's mind and proving that there is no need to do so, almost everyone gets busy on the proof.
“I know Mother named me after a railroad man, but it's too late now, I'm afraid. Much, much too late.”
“I'm old enough to have friends and contemporaries who have long since retired, and that's their prerogative - enough is enough; it doesn't mean a thing to me. But I haven't got any money, so, you know, I just keep on working.”