@MissA, I mean the idea that the market can take care of itself (i.e. that “government is the problem,” as Reagan said), that the market left to its own devices provides the best possible service, that any problems caused by companies/products will be ironed out because consumers are rational and will choose better companies/products.
Whereas, in reality, the market left to its own devices has a tendency for monopolization and fails to account for externalities (such as pollution), and consumers are rarely rational.