Ideas come when we do not expect them, and not when we are brooding and searching at our desks. Yet ideas would certainly not come to mind had we not brooded at our desks and searched for answers with passionate devotion.

Max Weber (1864-1920) German sociologist, philosopher, political economist [Maximilian Karl Emil Weber]

“Science as a Vocation [Wissenscahft als Beruf],” Speech, Munich University (1918) [tr. Gerth & Mills (1948)]
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Alt. trans.:

• "Ideas come when they are least expected, rather than while you are racking your brains at your desk. But, by the same token, they would not have made their appearance if we had not spent many hours pondering at our desks or brooding passionately over the problems facing us." [tr. Livingstone]
• "[Ideas] come, at any rate, when one does not expect them, not while racking one's brains and pondering at one's desk. Of course, the ideas would not have occurred to us without our having been through the state of racking our brains and being engaged in impassioned questioning." [tr. Wells (2018)]