Life Begins at Forty is a 1932 American self-help book by Walter B. Pitkin. Written during a time of rapid increase in life expectancy, it was very popular and influential. It was the #1 bestselling non-fiction book in the United States in 1933, and #2 in 1934, according to Publishers Weekly. No. 1 on The New York Times Nonfiction best seller list for 1 week, from the issue of October 9, 1933. Wiki link