I love the unexpected pleasures that await me as I scroll my daily sites for news, laughs, insight and inspiration. Many of you no doubt know of this site, but today’s post left me feeling like I needed to share. It’s one of my favorites to date, right up there with the one about Herman Melville on his birthday. Just in case you were ever curious about how such a compilation of words as the thesaurus ever came to be, here’s the scoop.

From The Writer’s Almanac:
It’s the birthday of the physician and lexicographer Peter Mark Roget, born in London, England (1779). He was a working doctor for most of his life, but he was also a Renaissance man, a member of various scientific, literary and philosophical societies. In his spare time, he invented a slide rule for performing difficult mathematical calculations, and a method of water filtration that is still in use today. He wrote papers on a variety of topics, including the kaleidoscope and Dante, and he was one of the contributors to the early Encylopaedia Britannica.

He was 61 years old and had just retired from his medical practice, when he decided to devote his retirement to publishing a system of classifying words into groups based on their meanings. Other scholars had published books of synonyms before, but Roget wanted to assemble something more comprehensive. He said, “[The book will be] a collection of the words it contains and of the idiomatic combinations peculiar to it, arranged, not in alphabetical order as they are in a Dictionary, but according to the ideas which they express.”

He organized all the words into six categories: Abstract Relations, Space, Matter, Intellect, Volition, Sentient and Moral Powers, and within each category there were many subcategories. The project took him more than 10 years, but he finally published his Thesaurus of English Words and Phrases in 1852. He chose the word “thesaurus” because it means “treasury” in Greek.

Roget’s Thesaurus might have been considered an intellectual curiosity, except that at the last minute Roget decided to include an index. That index, which helped readers find synonyms, made the book into one of the most popular reference books of all time. It is considered one of the great lexicographical achievements in the history of the English language, and it has been helping English students pad their vocabularies for more than 150 years.