[andrei_says_]

1. Today I learned ;)

2. I was writing about the abbreviation specifically, which was used in Heinkein’s book.

[fuzzfactor]

I first heard it in person as advice from people who were born in the 1890's and I think it was something that had been explained to them as children themselves.

Seemed to me it probably originated in New York City.

Heinlein was referencing a familiar but cynical saying which is an example that was intended to be kept in mind whether you understood the full implications or not.