During this time my intellectual ambitions were taking shape. I resolved not to adopt a profession, but to devote myself to writing. I remember a cold, bright day in early spring when I walked by myself in the Tiergarten, and made projects of future work. I thought that I would write one series of books on the philosophy of the sciences from pure mathematics to physiology, and another series of books on social questions. I hoped that the two series might ultimately meet in a synthesis at once scientific and practical.
Source:The Autobiography of Bertrand Russell, v.１, chap. 5: First marriage, 1967
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