If you want to succeed in business in any capacity - employee, manager, or owner - you must have a solid, comprehensive understanding of what business principles actually are and how they actually work.

The quickest and easiest way to screw up your life is to take on too much debt.

Email is 20-30 times more effective in generating a purchase than any other tool.

Business is essentially applied rationality: a systematic process of thinking that produces a real-world result. Instead of mortgaging your life to go to business school, it's possible to dramatically increase your knowledge of business on your own time and with little cost - without setting foot inside a classroom.

You can't make positive discoveries that make your life better if you never try anything new.

When you're feeling lost, take heart. It's just your brain gathering the information it needs to make good decisions.

Business schools don't create successful people. They simply accept them, then take credit for their success.

A good salesman, as the old (and politically incorrect) saying goes, can sell a refrigerator to an Eskimo. It's a cliché, but there's some truth to it: Inuit who live above the Arctic Circle use insulated refrigerators to keep their food from freezing in subzero temperatures