Consider this remarkably fair-minded post by Mario Rizzo:
“In the field of methodology Keynes and the Austrians agree that economics is a social science to which methods that have proved successful in the natural sciences should not be applied without careful inspection, and that, in particular, all attempts to ‘give numerical values’ to the parameters of economic models ignore the essential meaning of economic theory. It is hardly surprising that even here we find differences of accent and perspective, but, with the area of agreement so broad and significant, they do not amount to much ….It might come as a surprise to the various Austrian sympathizers (who think Austrian economics begins and ends with Mises and Rothbard) that their school includes the Lachmann wing and some of the moderate subjectivists who are able to appreciate Keynes, rather than engage in endless abuse.
Keynes concurs with Hayek’s misgivings about numerical values. In his letter to Harrod of 16 July 1938 we read ‘In chemistry and physics and other natural sciences the object of experiment is to fill in the actual values of the various quantities and factors appearing in an equation or a formula; and the work when done is once and for all. In economics that is not the case, and to convert a model into a quantitative formula is to destroy its usefulness as an instrument of thought’ ….
But Keynes’s mind also moves in another direction. ‘I also want to emphasize strongly the point about economics being a moral science. I mentioned before that it deals with introspection and with values. I might have added that it deals with motives, expectations, psychological uncertainties. One has to be constantly on guard against treating the material as constant and homogeneous. It is as though the fall of the apple to the ground depended on the apple’s motives, on whether it is worthwhile falling to the ground, and whether the ground wanted the apple to fall, and on mistaken calculations on the part of the apple as to how far it was from the centre of the earth’ (ibid, p. 300). Keynes sees in social facts manifestations of the human mind. While to Hayek it is the complexity of these facts, their multitude and diversity, that defies the attribution of numerical values to social concepts, to Keynes it is their mental character (‘mistaken calculations on the part of the apple’) that does so. Rather to the surprise of some of us, Keynes emerges as being more deeply committed to subjectivism than is his Austrian opponent” (Lachmann 1983: 256).
As I have pointed out before, Post Keynesianism has some affinities (but also major differences) with the radical subjectivist Austrian economics of Ludwig Lachmann (and Austrians influenced by him like O’Driscoll and Rizzo). You might think that this would be a starting point for building bridges, and O’Driscoll and Rizzo once in fact said so (see The Economics of Time and Ignorance, Oxford, UK, 1985, p. 9). I personally regard ThinkMarkets as the best Austrian blog on the net, miles ahead of the others.
But then I find the ignorant “pop” Austrians – ignorant even of the intellectual diversity of the Austrian school – who do nothing but foam at the mouth at the mention of Keynes’ name.
This ignorance extends to the inability to understand that the debate between Austrians and Keynes and his followers was intense in the 1930s and 1940s, and the Austrians lost that debate. The notion that Keynes was ignorant of Hayek or Austrian ideas is nonsense.