Essentially, Director and Levi (1956) demonstrated an unprecedented skepticism about the extension of monopoly power via exclusionary practices, such as tying arrangements or price discrimination, and a concomitant disdain for adjudication or legislation that regarded these practices as per se deleterious or per se illegal.

Philip Mirowski & Dieter Plehwe (eds.), The Road from Mont Pèlerin, loc. 1082