"Who's John Stossel?"
 
That was Virgil Rosanke's reaction when "20/20" interviewed him for one of my TV specials. Without Rosanke and others like him, I couldn't have a steak dinner tonight, but I and most of the people he makes dinners possible for are unknown to him. He makes our dinners possible anyway.

Is Virgil Rosanke a philanthropist? No. Is he a government worker? Not that either. He's just a guy who delivers propane to heat water for cattle to drink. Why does he do it? To make money.

If pursuing profit is greed, economist Walter Williams told me, then greed is good, because it drives us to do many good things. "Those areas where people are motivated the most by greed are the areas that we're the most satisfied with: supermarkets, computers, FedEx." By contrast, areas "where people say we're motivated by 'caring'" -- public education, public housing etc. -- "are the areas of disaster in our country. . . . How much would get done," Williams wondered, "if it all depended on human love and kindness?"

Greed gets people to cooperate. If you want to benefit from other greedy people, you have to make sure they benefit from you. Consider one of the wonders of our age, the supermarket. There are thousands of products on the shelves. How'd they get there?

When I posed that question about just one of those thousands of products -- a piece of beef I bought for my dinner -- I found a trail back to an Iowa farm. That's how I learned about Virgil Rosanke, and how he learned about me.

We taped David Wiese and his family, farmers in Manning, Iowa, as they put in 14-hour days fixing fences, digging ditches, harvesting hay, and feeding the cattle. They don't do it for me and my neighbors -- but I'm glad they do it.

"Do you think it's because they love people in New York?" Williams asked. "No, they love themselves. And by promoting their own self-interest, they make sure New Yorkers have beef."

The Wieses are just the first in a long series of people who, by caring about themselves, make sure I get my steak. Wanda Nelson keeps the packing house clean. Rosanke delivers propane. Other people slaughter the cattle and butcher the beef; they rely on people who make their knives, their overalls and their protective gear. Then there are the people who make the plastic that seals the meat, who run the machines that do the sealing, who pack the meat in boxes, make the boxes, inspect the boxes, and run the freezer facilities. Still other people track orders by bar code, which means they need the people who make the bar code machines. Eventually, packed steak is delivered to Randall Gilbert, a truck driver, who hauls it to New York.

No one person made my dinner possible. It took thousands of people to get me the food. And none of them did it for me. As economist Adam Smith put it, "It is not from the benevolence of the butcher, the brewer, or the baker that we expect our dinner, but from their regard to their own interest."

Rosanke and the others don't particularly care if some TV correspondent gets his steak, yet they cooperate to make it happen, motivated by self-interest -- what many call greed. Think about that next time you listen to my colleagues sneer at the "greed" and "selfishness" of private business. They don't realize that the institution they celebrate, government, is far less effective at serving humanity.

"In a free market, you get more for yourself by serving your fellow man," said economist Williams. "You don't have to care about him, just serve him. I'd feel sorry for New Yorkers in terms of beef. If it all depended on human love and kindness, I doubt whether you would have one cow in New York."

Does anything get done based on "human love and kindness"? Well, a nonprofit group called City Harvest collects donations of restaurants' surplus food for the poor. But where does that food come from? Greedy people like Virgil Rosanke produce it, and greedy restaurateurs buy it. Kindness can only give away the goods self-love provides.