Rule Breaker Investing is back with Great Quotes Vol. 2, and host David Gardner is sharing four of his favorite quotes.

Find out what Walt Whitman can teach us about investing, how The IT Crowd is pushing geek culture into the mainstream, what Warren Buffett's three I's of every business cycle (innovators, imitators, and idiots) can teach investors about the hype cycle, and how one of David Gardner's own quotes can show us how to make money in the stock market even when it goes down one out of every three years.

In this segment, Motley Fool co-founder David Gardner shares how Walt Whitman and F. Scott Fitzgerald can teach us critical lessons about making good decisions in the stock market.

Check out David's other favorite quotes:

A transcript follows the video.

This podcast was recorded on March 23, 2016. 

David Gardner: The first quote I want to lead off with this podcast comes from Walt Whitman:

Do I contradict myself? Very well. Then I contradict myself. I am large. I contain multitudes.

A great poet. I have to admit I never studied Whitman that much myself, even as an English major going through the University of North Carolina. We were probably more focused -- back then, anyway -- on English literature and not American poets.

The reason that this quote means a lot to me is because it reminds me of how to think about investing, which is that it's totally fine to have ideas at odds with each other and still decide to buy or to sell accordingly. In fact, you're going to be a better investor if you find yourself contradicting yourself as you go through the process of trying to figure out whether you want to buy this stock or not.

This kind of sentiment was similarly echoed by -- I won't quote him directly -- F. Scott Fitzgerald. Many will know F. Scott Fitzgerald's famous quote about how brilliance or genius is the ability to keep two opposed thoughts in the mind at the same time.

Whether we're talking about bulls and bears, long and short, buy or sell, the ability to keep contradictory thoughts in your mind at the same time -- to harbor them, to allow them to live there; not to be defensive or defend your own viewpoint, but to be open to the possibility that you're wrong, first of all, or that things might change for better or for worse from how you're seeing things; and to be open to directly contradictory viewpoints from others like friends around you who may really love that stock that you hate -- this is such an important part, not just of being a good investor, but, I think, of being a good citizen and a good human being.

"Do I contradict myself? Very well. Then I contradict myself. I am large." You are too, by the way. I'm not really that large. I'm about 5'10-3/4". By the way, that I say three-quarters shows that I have a slight chip on my shoulder that I didn't make 5' 11" or really 6'. I contain multitudes.

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