Robert A. Heinlein Quotes about Past

A generation which ignores history has no past — and no future.
Robert A. Heinlein (1987). “Time Enough for Love”, p.223, Penguin
Robert A. Heinlein (1987). “Starship Troopers”, p.159, Penguin
"The Moon Is a Harsh Mistress". Book by Robert A. Heinlein, Ch. 22, 1966.