The jokes about a mother-in-law are scarcely delicate, but the problem of a mother-in-law is extremely delicate. A mother-in-law is subtle because she is a thing like the twilight. She is a mystical blend of two inconsistent things — law and a mother. The caricatures misrepresent her; but they arise out of a real human enigma.
– What’s Wrong with the World (1910).