The idea that a bell rings to signal when investors should get into or out of the stock market is simply not credible. After nearly fifty years in this business, I do not know of anybody who has done it successfully and consistently. I don't even know anybody who knows anybody who has done it successfully and consistently. Yet market timing appears to be increasingly embraced by mutual fund investors and the professional managers of fund portfolios alike.
John C. BogleBut whatever the consensus on the EMH, I know of no serious academic, professional money manager, trained security analyst, or intelligent individual investor who would disagree with the thrust of EMH: The stock market itself is a demanding taskmaster. It sets a high hurdle that few investors can leap.
John C. BogleRely on the ordinary virtues that intelligent, balanced human beings have relied on for centuries: common sense, thrift, realistic expectations, patience, and perseverance.
John C. BogleIf it is hard to imagine that 20% of losses on the stock market, you should never participate
John C. Bogle