People
A man may be a fool and not know it – but not if he is married.
— H. L. Mencken
Behind the line May contain spoilers.
Our reading
An editorial interpretation.
A sardonic joke that a man can go through life a fool without realising it, unless he's married, in which case he'll be informed. The humour rests on marriage acting as a constant, unflattering mirror held up by a spouse.
Context reviewed