The mystic who refuses to use his brains is displaying not a virtue, as he believes, but a failing. Yet such a man has become stereotyped in the thought of most people as a type of man possessed of a flabby intellect. What they have not known is that there is another kind, the philosophic mystic, who seeks to develop his brain-power alongside of his mystical intuitions. Philosophy silences thought when it wants to feel inner peace or enter spiritual ecstasy, but it stimulates thought when it wants to understand this peace and that ecstasy.
-- Notebooks Category 20: What Is Philosophy? > Chapter 4: Its Realization Beyond Ecstasy > # 72