By contrast, efficiency argue that antitrust legislation should be changed to primarily benefit consumers, and have no other purpose. Free market economist Milton Friedman states that he initially agreed with the underlying principles of antitrust laws (breaking up monopolies and oligopolies and promoting more competition), but that he came to the conclusion that they do more harm than good. Thomas Sowell argues that, even if a superior business drives out a competitor, it does not follow that competition has ended:  Alan Greenspan argues that the very existence of antitrust laws discourages businessmen from some activities that might be socially useful out of fear that their business actions will be determined illegal and dismantled by government. In his essay entitled "Antitrust," he says: "No one will ever know what new products, processes, machines, and cost-saving mergers failed to come into existence, killed by the Sherman Act before they were born. No one can ever compute the price that all of us have paid for that Act which, by inducing less effective use of capital, has kept our standard of living lower than would otherwise have been possible." Those, like Greenspan, who oppose antitrust tend not to support competition as an end in itself but for its results—low prices. As long as a monopoly is not a coercive monopoly where a firm is securely insulated from "potential" competition, it is argued that the firm must keep prices low in order to discourage competition from arising. Hence, legal action is uncalled for and wrongly harms the firm and consumers. Thomas DiLorenzo, an adherent of the Austrian School of economics, found that the "trusts" of the late 19th century were dropping their prices faster than the rest of the economy, and he holds that they were not monopolists at all. Ayn Rand, the American writer, provides a moral argument against antitrust laws. She holds that these laws in principle criminalize any person engaged in making a business successful, and, thus, are gross violations of their individual expectations. Such laissez faire advocates suggest that only a coercive monopoly should be broken up, that is the persistent, exclusive control of a vitally needed resource, good, or service such that the community is at the mercy of the controller, and where there are no suppliers of the same or substitute goods to which the consumer can turn. In such a monopoly, the monopolist is able to make pricing and production decisions without an eye on competitive market forces and is able to curtail production to price-gouge consumers. Laissez-faire advocates argue that such a monopoly can only come about through the use of physical coercion or fraudulent means by the corporation or by government intervention and that there is no case of a coercive monopoly ever existing that was not the result of government policies.