This 1979 interview of Milton Friedman by Phil (forgive the hair) Donahue is purest gold.
The two minute clip below is from a set of five ten-minute videos.
"The world runs on individuals pursuing their self interest. Is there some society that doesn't run on greed?
The only places where the masses have escaped from the kind of grinding poverty you are talking about are where they have had capitalism and largely free trade.
Do you think the communist commissar rewards virtue? That Hitler rewarded virtue? That American presidents reward virtue? Do they choose their appointees on the basis of virtue or on the basis of political clout? Is it really true that political self-interest is nobler somehow than economic self-interest? Where in the world are you going to find these angels to organize society for us?"
(The only system I trust is one that works with people as they are, not as they should be).