Barry Goldwater, speech accepting nomination for president, Republican national convention, San Francisco, California (July 16, 1964). Congressional Record, July 21, 1964, vol. 110, p. 16388. Senator Goldwater comments that the remark was not original with him: "In fact, I believe Cicero used it in some form at one time, and I have been able to trace it rather faintly back to some of the early Greeks so, while I was very proud of the fact that I made the speech, it's certainly not original".https://en.wikiquote.org/wiki/Extremism