“Why Richard von Mises had no Clue about Keynes’s Approach,” http://www.amazon.com/gp/richpub/syltguides/fullview/R30TUJZSINCMJHThese bear careful reading, especially the second on Rothbard.
“Rothbard’s Many Errors about Keynes and Probability,” http://www.amazon.com/gp/richpub/syltguides/fullview/R83TIX8MB95QW
A sample:
‘Rothbard has made at least 10 errors in the space of 5 short paragraphs. The first 4 errors occur in Rothbard’s claim that “Keynes’s Treatise championed the classical a priori theory of probability, where probability fractions are deduced purely by logic and have nothing to do with empirical reality.” First, Keynes’s logical theory of probability is based on George Boole’s 1854 The Laws of Thought. It has nothing to do with the Classical theory of Laplace, whose Principle of Non Sufficient Reason Keynes decimated in the A Treatise on Probability in chapter 4. Second, all of Keynes’s probabilities are conditional. Third, the hypothesis, h, is always related to empirical evidence, e. Thus, a probability is always of the form P(h/e). Fourth, the claim that the “probability fractions are deduced purely by logic and have nothing to do with empirical reality” is simply bizarre as Keynes’s probabilities, in general, are intervals and are not sharp or point probabilities (fractions) except in the limiting case where the weight of the evidence, w, = or approaches 1. The condition that w = 1 or approaches 1 only occurs in the physical and biological sciences. Fifth, the probability relation is not deduced. It is perceived by the decision maker based on intuition, analogy and pattern recognition. …. Eighth, the claim that “… Keynes’s a priori theory was demolished by Richard von Mises (1951) in his 1920s work, ‘Probability, Statistics, and Truth’ is a bad joke. Richard von Mises incorrectly identifies Keynes as a subjectivist and committed the fatal error of overlooking Keynes’s requirement that all probabilities require that w > 0. Richard von Mises claim that Keynes specified probabilities for the case where w = 0 means that he never read the book he claimed to be discussing. Nineth, Rothbard’s claim that “Mises demonstrated that the probability fraction can be meaningfully used only when it embodies an empirically derived law of entities which are homogeneous, random, and indefinitely repeatable” had already been done by Keynes in chapters 8 and 33 of the TP. Keynes would have added the terms uniform and stable as he did in his debate with Tinbergen in 1939–40 in the Economic Journal. Ninth, the claim that “probability theory can only be applied to events which, in human life, are confined to those like the lottery or the roulette wheel” is only correct if one is using mathematical probability. Keynes includes interval probability as the main way in which people use probability. … Rothbard’s scholarship can only be characterized as pathetic.’Comments are welcome: I have no hesitation in saying that the finer, technical points of probability theory are not my area.
“Rothbard’s Many Errors about Keynes and Probability,” http://www.amazon.com/gp/richpub/syltguides/fullview/R83TIX8MB95QW