“Except for Marxian theories, nearly all modern theories of the business cycle have essential elements that trace back to Knut Wicksell's turn-of-the-century writings on interest and prices. Austrians, New Classicists, Monetarists, and even Keynesians can legitimately claim a kinship on this basis. Accordingly, the recognition, that both the Austrians and the New Classicists have a Swedish ancestry does not translate into a meaningful claim that the two schools are essentially similar. To the contrary, identifying their particular relationships to Wicksellian ideas, like comparing the two formally similar business-cycle theories themselves, reveals more differences than similarities. … [T]o establish the essential difference between the Austrians and the New Classicists, it needs to be added that the focus of the Austrian theory is on the actual market process that translates the monetary cause into the real phenomena and hence on the institutional setting in which this process plays itself out.The New Classicists deliberately abstract from institutional considerations and specifically deny, on the basis of empirical evidence, that the interest rate plays a significant role in cyclical fluctuations (Lucas 1981, p. 237 151–1). Thus, Wicksell's Interest and Prices is at best only half relevant to EBCT. … Taking the Wicksellian metaphor as their cue, the New Classicists are led away from the pre-eminent Austrian concern about the actual market process that transforms cause into effect and towards the belief that a full specification of the economy's structure, which is possible only in the context of an artificial economy, can shed light on an effect whose nature is fundamentally independent of the cause.”

Pages 98–99.
"New Classical and Old Austrian Economics", 1991