… is from pages 260-261 of economist Lionel Robbins’s insightful and still-relevant 1937 book, Economic Planning and International Order:
It is wrong to claim, for a liberal system, continuous achievement of the perfect competitive equilibrium of pure theory. Indeed it is probable that some of the current strictures on such a system arise from excessive preoccupation with these abstractions, to the neglect of investigation of the way in which institutions which limit competition will actually work in practice. What can be claimed for the system in this respect is not that it eliminates all those indivisibilities of factor combination and imperfections of the market which give rise to quasi-monopolistic positions, but rather that, if there is no statutory support for restrictive practices, and if the law is properly framed, any attempt to exploit these positions, outside very narrow margins, will be frustrated by new competition. The wider the market and the freer the range of choice, the smaller will these imperfections be.