At the end of those five minutes, I had become a completely different person. ... Having been an Imperialist, I became during those five minutes a pro-Boer and a Pacifist. Having for years cared only for exactness and analysis, I found myself filled with semi-mystical feelings about beauty, with an intense interest in children, and with a desire almost as profound as that of the Buddha to find some philosophy which should make human life endurable.
Source: The Autobiography of Bertrand Russell, v.１, chap. 6: Principia Mathematica, 1967
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