I underwent a process of rejuvenation, inaugurated by Ottoline Morrell and continued by the War. It may seem curious that the War should rejuvenate anybody, but in fact it shook me out of my prejudices and made me think afresh on a number of fundamental questions. It also provided me with a new kind of activity, for which I did not feel the staleness that beset me whenever I tried to return to mathematical logic.
Source: The Autobiography of Bertrand Russell, v.2（1968）p.15
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