Dale Carnegie

Dale Carnegie ( KAR-nig-ee; spelled Carnagey until c. 1922; November 24, 1888 – November 1, 1955) was an American writer and teacher of courses in self-improvement, salesmanship, corporate training, public speaking, and interpersonal skills. Born into poverty on a farm in Missouri, he was the author of How to Win Friends and Influence People (1936), a bestseller that remains popular today. He also wrote How to Stop Worrying and Start Living (1948), Lincoln the Unknown (1932), and several other books.

One of the core ideas in his books is that it is possible to change other people's behavior by changing one's behavior towards them.

Notable works: How to Win Friends and Influence People, How to Stop Worrying and Start Living, Public Speaking and Influencing Men in Business Education: American Academy of Dramatic Arts, Maryville High School

Source: Wikipedia — https://en.wikipedia.org/wiki/Dale_Carnegie