Some people hate me because I defend free markets. Once someone accosted me on a New York City street and said, "I hope you die soon."

Why the hostility to commerce? What could be more benign than the freedom to trade with whomever you wish?

I suspect ignorance about economics leads many to believe that when two people exchange goods and money, one wins and the other loses. If rich capitalists profit, the poor and the weak suffer.

That's a myth.

How many times have you paid $1 for a cup of coffee and after the clerk said, "thank you," you responded, "thank you "? There's a wealth of economics wisdom in the weird double thank-you moment. Why does it happen? Because you want the coffee more than the buck, and the store wants the buck more than the coffee. Both of you win.

Economists have long understood that two people trade because each wants what the other has more than what he already has. In their respective eyes, the things traded are unequal in value. But this means each comes out ahead, having given up something he wants less for something he wants more. It's just not true that one gains and the other loses. If that were the case, the loser wouldn't have traded. It's win-win, or as economists would say, positive-sum.

We experience this every time we have that double thank-you moment in a store or restaurant.

It doesn't matter that you wish the price of coffee were lower. We want the price of everything to be lower (except the price of what we're selling, whether it's our products or labor). What matters is that you bought the coffee for a buck.

The story doesn't change if you buy from someone in another city or another state. It doesn't change even if you buy from someone in another country.

That's why I worry when I hear politicians say things like, "I believe in free trade, but it has to be fair trade". That particular quote is from a presidential contender, Mike Huckabee, former governor of Arkansas. Continued...