The Spartans were fans of brevity.

In his book The Warrior Ethos, Steven Pressfield tells the story of a Spartan general who captured a city. "His dispatch home said, 'City taken.' The magistrates fined him for being verbose. 'Taken,' they said, would have sufficed."

People are persuaded by complexity. It gives the impression of brilliance. But if you can't explain something simply you probably don't understand it at all. 

Years ago, journalist Jason Zweig was asked if he could summarize his investment philosophy in 10 words or less. At first he laughed and said no.

With some more thought, he came up with, "Anything is possible, and the unexpected is inevitable. Proceed accordingly." He went on to ask investors to do the same and they came up with some amazing responses. 

I love this exercise. My own would be: "Worry only when you think you have it figured out."

I asked my investing friends to sum up their investment philosophy in 10 words. Here's what I got. 

Tom Gardner, Motley Fool: "Find remarkable leaders on a lifelong mission -- buy and add." 

Bill Mann, Motley Fool Asset Management: "Seek to invest alongside great managers. Then, be patient."

Josh Brown, CNBC, The Reformed Broker: "Roses are red, violets are blue. I don't know what will happen and neither do you."

Barry Ritholtz, Bloomberg: "Keep it simple, do less, and manage your stupidity." 

Robert Brokamp, Motley Fool: "Diversification reduces risk, increases predictability, and boosts returns." 

Michael Batnick, Ritholtz Wealth Management: "Avoiding catastrophic mistakes matters more than constructing the 'perfect portfolio.'"

Tim Hanson, Motley Fool: "Buy the awesome at prices that don't reflect their awesomeness."

Cullen Roche, Pragmatic Capitalism: "Low-fee, tax-efficient, index-based global-macro asset allocation."

Rich Greifner, Motley Fool: "Think long term, stay patient, and seek asymmetric returns."

Eddy Elfenbein, blogger, Crossing Wall Street: "Be patient and ignore fads. Focus on value. Never panic."

Michael Kitces, financial adviser: "Invest long term, don't speculate. But don't ignore market valuations."

Ben Carlson, author of A Wealth of Common Sense: "Less is more. Process over outcomes. Behavior is the key."

James Early, Motley Fool: "Exploit the cognitive weaknesses of others." 

Harold Pollack, University of Chicago: "Save 15-20%. Low-fee Indexes. Pay off plastic. Maximize 401(k)."

Ron Gross, Motley Fool "Buy solid companies with a margin of safety and hold."

Tren Griffin, blogger, 25iq: "Rationally purchase assets at prices creating a margin of safety."

Jeff Fischer, Motley Fool: "Own stocks to compound. Use options for income. Short failures."

Bryan Hinmon, Motley Fool Asset Management: "Own compounders. Buy smart. Be patient."

Justin Wolfers, economist, University of Michigan: "Save money. Avoid costly advice. Diversify widely."

David Gardner, Motley Fool: "Use my six Rule Breaker traits. Buy to hold."

Matt Koppenheffer, Motley Fool Germany: "Seek differentiated, well-managed, customer-oriented businesses. Buy when undervalued. Own long term."

Seth Jayson, Motley Fool: "Be safe, keep your costs low, and don't overthink."

Craig Shapiro, venture capitalist: "Aligning self interest with broader interest will generate exponential returns."

Patrick O'Shaughnessy, OSAM: "Find pessimistic outlooks. Dig deeper. Put wax in your ears."

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