Post Keynesian Economics Is Based on Joan Robinson’s Many Canards About Supposed Gaping Holes in Keynes’s Theory: The Real Problem Is Gaping Holes and Gross Ignorance in the Post Keynesian Understanding of Keynes’s a Treatise on Probability

Abstract

There is no Post Keynesian economist or allied philosopher who can comprehend the following, basic 100 year old fact-Keynes, building on Boole ‘s The Laws of Thought (1854), created an interval valued approach to probability, as well as a decision weight approach, the c coefficient, that re-expresses interval valued probability as non additive and non linear probability, that has nothing to do with radical uncertainty or ordinal probability as asserted continuously for 50 years. Consider the example of R. Skidelsky. R. Skidelsky was very much like Joan Robinson in his academic skills, upon whom he has built his view of Keynes’s contributions. R. Skidelsky, like Joan Robinson, has admitted many times that he is mathematically illiterate, inept, and innumerant. This self admitted fact made Skidelsky very susceptible and receptive to the Frank P. Ramsey myth, recently resurrected by C. MIsak (2020). This myth purports that Ramsey, an 18 year old teenager who came to Cambridge University in 1921, was able to convince Keynes in 1922 that his logical theory of probability, as presented in his 1921 A Treatise on Probability, was full of logical, epistemological and philosophical errors that demolished the entire logical foundation and edifice of Keynes’s theory. Of course, given the fact that Keynes’s theory is built directly on a foundation and edifice of George Boole’s mathematical propositional logic and algebra,which Ramsey (nor any other supporter of Ramsey, such as R.B. Braithwaite) dared not challenge at any time in his lifetime, the belief that Keynes, who had used his approach to approximation and inexact measurement in his Indian Currency and Finance and Economic Consequences of the Peace successfully, would accept Ramsey’s purely academic theory based on additivity and linearity, which Keynes knew did not hold at all in the real world of decision making involving missing evidence and vague, conflicting knowledge, is simply silly. Keynes,of course, realized that Ramsey’s great formal, intellectual skills would make him a great academic thinker. The acceptance by all Post Keynesians and heterodox economists, that Keynes capitulated, either in part or wholly, to Ramsey, has led to a complete failure to properly connect the Keynes of the A Treatise on Probability to the Keynes of the General Theory. This is very similar to the failure of Adam Smith academics to properly connect the Smith of The Theory of Moral Sentiments to the Smith of The Wealth of Nations. Both Keynes’s and Smith’s are, of course, identical in both books. The Ramsey myth has been continually promulgated since 1921. Misak’s 2020 book on Ramsey continues to make assertions about Keynes which are directly contradicted by Keynes himself. The best exposition that explodes the Ramsey myth is the Keynes-Townshend correspondence over the TP of 1937-38, where non numerical probability, weight of the evidence, and the logical theory of probability, and the relation to the GT are covered. There is no mention made of Frank Ramsey or the subjective theory of probability by Keynes or Townshend. The elimination of the Frank Ramsey myth is a necessary step that must be taken before any progress can be made on understanding the linkages between the TP and GT. From Hahn and Skidelsky in 1986 to Walsh in 2001 to Togati in 2020, we can see that the real problem is not any gaps in Keynes’s theory, but the blindness of Post Keynesian and heterodox economists regarding the TP and GT, who are either unable or unwilling to read the TP and/or chapters 20, 21 and appendix to chapter 19 of the GT.