“Reason alone does not suffice.”

Have One On Me (2010)

Remarks to British government minister Lord Halifax at Berchtesgaden (19 November 1937), quoted in Ivone Kirkpatrick, The Inner Circle (1959), p. 97 and Andrew Roberts, ‘The Holy Fox’: The Life of Lord Halifax (1997), p. 72
1930s

Academy of Achievement interview (1991)
Context: Reason alone will not serve. Intuition alone can be improved by reason, but reason alone without intuition can easily lead the wrong way. They both are necessary. The way I like to put it is that when I have an intuition about something, I send it over to the reason department. Then after I've checked it out in the reason department, I send it back to the intuition department to make sure that it's still all right. That's how my mind works, and that's how I work. That's why I think that there is both an art and a science to what we do. The art of science is as important as so-called technical science. You need both. It's this combination that must be recognized and acknowledged and valued.

[Stacy McGaugh, http://astroweb.case.edu/ssm/mond/inthon.html, "Intellectual Honesty, The Mond Pages"] at astroweb.case.edu. Accessed 2014.

Section 1 : Give Responsibility to Vitally Necessary Work!
The Mass Psychology of Fascism (1933), Ch. 10 : Work Democracy
Context: Natural work democracy is politically neither "left" nor "right." It embraces anyone who does vital work; for this reason, its orientation is only and alone forward. It has no inherent intention of being against ideologies, including political ideologies. On the other hand, if it is to function, it will be forced to take a firm stand, on a factual basis, against any ideology or political party which puts irrational obstacles in its path. Yet, basically, work democracy is not "against," as is the rule with politics, but "for"; for the formulation and solution of concrete tasks.

La razón no grita, la razón convence.
Attribution inscribed on the memorial statue in the Puerto Rican Capitol (see right).
Attributed

Cartoon caption, The New Yorker (27 July 1935)
Borrowing from Blaise Pascal, Pensées, 1670 (published posthumously): ""Le coeur a ses raisons que la raison ne connaît point""
Cartoon captions