<p>Investing books are all well and good, but life offers myriad sources of more inspiring material. Today David turns to gurus and geeks to find investing lessons that you probably won't learn in business school. This is the second entry in our recurring <em>Great Quotes</em> series which debuted last December.</p>

March Mailbag

David Gardner, co-founder of The Motley Fool, is among the most respected and trusted sources on investing. As a best-selling author, hugely successful stock picker, and financial authority, David has led The Motley Fool’s growth into a worldwide investment and financial advisory services company.
Each week David shares his insights into today's most innovative and disruptive publicly traded companies -- and how to profit from them by following his signature “Rule Breaker Investing” principles.