If you remember the Sixties, you weren't there.

Attributed to Slick in Bangkok Babylon (2006) by Jerry Hopkins, p. 217, and elsewhere, this was also attributed to Paul Kantner in The New Yorker, Vol. 67 (1991), Dennis Hopper in Roger Ebert's Movie Home Companion (1992), and in various books to numerous others, including Judy Collins, George Harrison, and comedian Robin Williams.

The cite is a two-line article in the Comedy column of the Los Angeles Times in 1982 | EXIT LINE: Comedian Charlie Fleischer observes: “If you remember the ’60s, you really weren’t there.” | (QuoteInvestigator.com)