Stone himself was born in Chicago and was just 3 when his father died. He started his business career at age 6, when he started selling newspapers to help support himself and his mother. At age 16, he journeyed to Detroit to help out his mother at an insurance company she'd opened there. Soon, he was making $100 a week selling casualty insurance. Stone was soon a prime example of a character right out of the Horatio Alger stories, in which poor boys make good. In the late 1920s, Stone built the Combined Insurance Company of America, and by 1930, he had over 1000 agents selling insurance for him across the United States. By 1979, Stone’s insurance company exceeded $1 billion in assets. His company merged with the Patrick Ryan Group to form the Aon Corporation in 1987. Combined Insurance Company is one of Aon's largest subsidiaries. Above all, Stone emphasized using a "positive mental attitude" to make money for himself, and for millions of people who read his books. In 1960, Stone teamed up with Napoleon Hill to author Success Through a Positive Mental Attitude.