Some fundamental differences between IYLM and ISLM: reply to Fuller
回应Fuller的评论，指出ISLM模型基于凯恩斯所拒绝的新古典框架，而凯恩斯提出的货币生产经济理论在利率决定、投资机制和方法论上与之根本不同。
Edward Fuller’s Comment (2017) raises several fundamental issues. Since their adequate discussion exceeds the permitted space, our brief rejoinder concerns only the central claims. The Comment neglects two key background issues. At a theoretical level, Keynes constructed a new theory that rejected orthodoxy, as attested by his lecture notes, preliminary drafts and the GT (Rymes, 1988, 1989; Keynes, 1973). Instead of deploying real-exchange (and neutral money) economies, pure price mechanisms, self-adjustment to unique long-period full employment equilibrium, the loanable funds theory (LFT) of the (real or natural) interest rate (ir), the determination of investment by LFT and agents endowed with perfect knowledge and abilities, he advanced a monetary production economy, self-adjustment to non-optimal equilibria (long and short period), the liquidity preference theory of the (nominal) interest rate (in), investment determination via comparisons of mecs with in and agents endowed with limited knowledge and abilities. Further, at a methodological level, his new theory markedly departed from neoclassical orthodoxy, for it reposed on different ideas concerning assumptions, theory and model construction, causality and time, for example. Both these framework-related differences are crucial and should not be ignored. In both respects ISLM rests on the old framework that Keynes rejected.