In 1993, Buffett told his shareholders: “By periodically investing in an index fund, for example, the know-nothing investor can actually outperform most investment professionals. In “The Little Book of Common Sense Investing,” by Vanguard founder and former CEO John Bogle, Buffett said, “A low-cost index fund is the most sensible equity investment for the great majority of investors.” As befitting such a legendary investor, Buffett put his money where his mouth was in 2007, betting $1 million that the S&P 500 would outperform hedge funds over the following 10 years.