John Bogle is the legendary founder of Vanguard, the giant mutual fund company. He's an industry pioneer, and within the mutual fund business considered a certified curmudgeon. He's also one of the best friends the individual investor has had in recent decades. The reason is that Bogle opened up index investing to the individual investor with the Standard & Poor's 500 equity index fund in 1976.

He's out with a new book, The Little Book of Common Sense Investing. I've been reading it, and it's good. The first sentence is a gem: "Successful investing is all about common sense." He convincingly explains what he means by financial commonsense over the next 214 pages. Buy it. Read it. Bogle is good for your financial health.

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