But markets can produce unintended harms as well as benefits. Desirable transactions don’t always produce desired market outcomes. In logic this is called “the fallacy of composition”: Aggregates can be simple or complex, so the properties of parts needn’t apply to wholes. Here’s a silly example: All atoms in an apple are invisible; therefore, the apple is invisible. Claims about free markets can be a world-threateningly serious example. The idea that markets composed of voluntary, so assumed to be desirable, and locally “rational” decisions aggregate to “rational” and desirable outcomes is empirically false. Few buy coffee intending to pollute. But the parts of markets together create (collectively undesirable) pollution. - http://bigthink.com/errors-we-live-by/market-lovers-commit-the-fallacy-of-composition