Having retired in 1848 from the office of Secretary of The Royal Society, a position he had held for more than 20 years, physician and polymath P. M. Roget set himself to the pursuit of his lifelong avocation, philology, the study of words. 4 years later, in 1852, he published the first thesaurus to bear his name, the
Roget's Thesaurus of English Words and Phrases, which was comprised of nearly 1000 categories, or classes, of words, encompassing something around 10,000 individual entries. Never out of print since first publication, the work has expanded almost logarithmically, and Roget's name itself has become synonymous with "Thesaurus".
Interestingly, a research paper he wrote in 1824 provided the functional basis for what today we know as movies, though beyond broaching the underlying concept, he apparently lost interest, not again visiting the idea, which was left for others to further expand and refine. Following his funeral in 1869, he was known to have taken no volitional, active role in anything else. It safely may be assumed that any soul Roget may have possessed had been parked somewhere, if souls may be parked, for 3/4ths of a century when that 1935 edition of Roget's Thesaurus rolled off the presses.