What harm is Capitalism?

If Capitalism is defined as the combination of trade and property rights, then what is the alternative?

Few people will argue that trade is not a good thing, or at least not harmful, and the argument about property rights is somewhat redundant since this is a matter of opinion more than belief. So, if there is no real alternative why is it opposed when no better solution is suggested?

To react to Capitalism merely by arguing that the Government should be given the money is not really a true argument since there is clearly no justification in doing that. If Capitalism is not harmful (and it has not been shown to be so) then let people be free to practice it, if they choose.