the economic analysis of competition policy along this scenario.

How to distinguish the private sphere, over which private agents should be basically free to compete with each other for the promotion of their own private objectives, from the public sphere, over which the government authority is within its jurisdiction to take public actions by itself, or regulate the actions of private agents in accordance with the socially agreed public objectives, is a deep and old issue; it can be traced back at least to John Locke and John Stuart Mill in England, and Benjamin Constant and Alexis de Tocqueville in France. Although the recognition that “a frontier must be drawn between the area of private life and that of public authority [Berlin (1969, p.124)]” is certainly not new, many attempts to provide a principle for drawing a frontier to this effect proved to be rather futile. Such an attempt goes all the way back to Mill’s On Liberty [Mill (1859/1977, p.276)], where he posed this issue in his idiosyncratic manner: “What … is the rightful limit to the sovereignty of the individual over himself? Where does the authority of society begin? How much of human life should be assigned to individuality, and how much to society?” Mill’s own answer to this crucial problem was a famous, but deceptively simple, principle: “Each will receive its proper share, if each has that which more particularly concerns it. To individuality should belong the part of life in which it is chiefly the individual that is interested; to society, the part which chiefly interests society.” Unfortunately, Mill’s “simple principle” to this effect seems to have posed more problems than it settled, as “[m]en are largely interdependent, and no man’s activity is so completely private as never to obstruct the lives of others in any way. ‘Freedom for the pike is death for the minnows’; the liberty of some must depend on the restraint of others [Berlin (1969, p.124)].” These difficulties become all the more serious when our focus is shifted to the freedom of competition for private enterprises. It is no wonder that the design and implementation of the fair game of competition have been the subject of harsh dispute.

Suppose, for the sake of argument, that a proper boundary line between the private sphere and the public sphere could be somehow drawn. Even then, it does not follow that the government authority in charge of competition policy could relax and be indifferent to what private agents --- individuals and private enterprises --- would do within their respective private spheres for at least two reasons.

In the first place, the government authority has the major task of designing the fair market game, which private agents are entitled to participate and play on their own initiatives, and seeing to it that all the participants faithfully observe their obligation of fair play. If there are infringements on the obligation of fair play, the government authority in charge of competition policy should rectify this divergence from the proper play of the game. It is to cope with this major task efficiently and effectively that the competition policy authority must legislate the competition laws, monitor the performance of market participants and, if need be, enforce the