By this time, it was becoming necessary to think in earnest about my Fellowship dissertation, which had to be finished by August, so we settled down at Fernhurst, and I had my first experience of serious original work. There were days of hope alternating with days of despair, but at last, when my dissertation was finished, I fully believed that I had solved all philosophical questions connected with the foundations of geometry. I did not yet know that the hopes and despairs connected with original work are alike fallacious, that one's work is never so bad as it appears on bad days, nor so good as it appears on good days.
Source: The Autobiography of Bertrand Russell, v.１, chap. 5: First marriage, 1967
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