Investment guru Jack Bogle gives some common-sense advice to savvy investors very similar to many lottery-advertising slogans: you have to play to win.

The Vanguard founder and former CEO advises that investors shouldn't try to time the market. "Never, never, never be in or out of the market. Always be in at a certain level," he told CNBC.

Bogle explained that many investors sold their stocks when markets took a severe fall during the 2008 financial crisis, and these people missed out on all or part of the market's dramatic rebound since then, CNBC.com explained.

"It shows you when you act on the emotions of the marketplace you're making a big mistake," he said. "Stay the course, don't let these changes in the market, even the big one [like the financial crisis] … change your mind and never, never, never be in or out of the market. Always be in at a certain level," he said.

Bogle, 89, said he keeps 50 percent of his investments in stocks.

"Never be out and think you can get back in because your emotions will defeat you totally," he said. "Short-term betting is not a good way to go."

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