I've never met anybody who's had a flashback in my life and I took millions of trips in the Sixties, and I've never met anybody who had any problem. I've had bad trips, but I've had bad trips in real life. I've had a bad trip on a joint. I can get paranoid just sitting in a restaurant; I don't have to take anything.
"The Beatles Anthology" by The Beatles, (p. 180), 2000.