The Strangest Secret was a 1957 spoken word record by Earl Nightingale, which sold over one million copies and received the first Gold Record for the spoken word and which helped launch the fields of business motivation and audio publishing. It was later adapted into print and video forms.
In 1950, Earl Nightingale was inspired by the words “we become what we think about” in Napoleon Hill’s book, Think and Grow Rich, around the same time he bought an insurance agency. He provided weekly motivational speeches to the agency’s sales staff. In 1956, he recorded a motivational speech to be played while he was on vacation. Nightingale’s employees spread word of the speech, and demand for the recording grew so large that he and friend Lloyd Conant formed the Nightingale-Conant Corporation to manage sales.