Legendary money manager Ken Fisher outlines the most common-and costly-mistakes investors make.

Small cap stocks are best for all time. Bunk!
A trade deficit is bad for markets. Bunk!
Stocks can't rise on high unemployment. Bunk!

Many investors think they are safest following widely accepted Wall Street wisdom-but much of Wall Street wisdom isn't so wise. In fact, it can be costly bunk.

In Debunkery: Learn It, Do It, and Profit From It-Seeing Through Wall Street's Money-Killing Myths, Ken Fisher-named one of the 30 most influential individuals of the last three decades by Investment Advisor magazine-details why so many investors fail to get the long-term results they desire. The short answer is many investors fail to question if what they believe is true-and are therefore blinded by tradition, biases, ideology, or any number of cognitive errors.

Your goal as an investor shouldn't be to be error-free-that's impossible. Rather, to be more successful, you should aim to lower your error rate. Debunkery gets you started by debunking 50 common myths-but that's just the beginning. It also gives you the tools you need to continue to do your own debunkery for the rest of your investing career.