Peter Mark Roget (1779-1869) studied medicine at Edinburgh University from the age of 14. In 1805 Roget started compiling a thesaurus which he kept a private document for almost 50 years. Roget eventually published 'Roget's Thesaurus of English Words and Phrases' in 1852 and the book has never been out of print since. Roget was also instrumental in establishing the University of London.
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