I finished this first draft of The Principles of Mathematics on the last day of the nineteenth century - i.e. December 31, 1900. The months since the previous July had been an intellectual honeymoon such as I have never experienced before or since. Every day I found myself understanding something that I had not understood on the previous day. I thought all difficulties were solved and all problems were at an end. But the honeymoon could not last, and early in the following year intellectual sorrow descended upon me in full measure.
Source: My Philosophical Development, chap. 6,1959
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