It's a basic fact of life that many things "everybody knows" turn out to be wrong.
Acknowledge the complexity of the world and resist the impression that you easily understand it.
People are too quick to accept conventional wisdom, because it sounds basically true and it tends to be reinforced by both their peers and opinion leaders, many of whom have never looked at whether the facts support the received wisdom.
Jim Rogers is a smart investor who co-founded the Quantum Fund with George Soros in 1973. By 1983 the fund gained more than 4000 percent.