It’s the birthday of doctor and mathematician Peter Mark Roget (1779-1869), best known today for his Thesaurus of English Words and Phrases (1852), a little something he knocked together in his retirement.

Roget was born in London to the son of a Swiss clergyman and the daughter of a jeweler; his father died when Roget was only about four, and his mother, possibly a touch paranoid, moved the family around a lot. Roget started studying medicine at the tender age of 14 at the University of Edinburgh and graduated in 1798. He then practiced medicine, took on private students (with whom he traveled), and contributed to several scientific fields, including optics. In 1815 he invented a slide rule to help calculate the roots and powers of numbers, which then influenced subsequent slide rules used until someone invented the calculator. (I’m going to be hearing about this tonight. Nothing gets my husband excited quite like a really fine slide rule. I am not joking.)

All this time, Roget had a habit of jotting down words and phrases in a notebook that he carried with him—not just a list, but an “indexed catalogue of words.” Evidently he struggled with depression, and the list-making was possibly a coping mechanism. (In addition to suffering from the early deaths of both parents, Roget experienced tragedy when his uncle and father figure died by slitting his own throat in Roget’s presence.) When Roget retired from medicine in 1840, he got serious about his thesaurus and published it 12 years later. He was not the first to list synonyms and antonyms, but he was the first to classify things in his particular way, organizing his first edition around six categories evidently based on Aristotle: abstract relations; space; the material world; the intellect; volition; and sentient and moral powers.

Roget truly loved the English language, which has more than 500,000 words in the OED (not including 400,000 technical terms), kind of kicking other languages’ butts such as French and German, which check in at a mere 100,000 and 185,000 words. (I counted. You would not believe how long it has taken me to write this post.) Roget said, “Every workman in the exercise of his art should be provided with proper implements. The writer employs for the accomplishment of his purposes the instrumentality of words. It is therefore essential to his success that he be provided with a copious vocabulary.”

Roget’s thesaurus has never been out of print and has sold more than 30 million copies.

EXTRA FUN BONUS SUGGESTION: Go to this website, https://www.visualthesaurus.com/ , type in a word, and watch in delight as a moving array of synonyms appears, floating around the word in a halo of inspiration. It’s surprisingly fun to play around with and can be very useful.

Have a fine Friday employing the English language for great and edifying deeds and stay scrupulously honest to the data.