Book Reviews

05 julho, 2007

123) Skidelsky's Keynes, in one volume

Uma crítica devastadora, contra apenas um aspecto da minumental biografia de John Maynard Keynes por Lord Robert Skidelsky.

John Maynard Keynes: 1883-1946: Economist, Philosopher, Statesman
Robert Skidelsky
Paperback: 1056 pages
Publisher: Penguin (Non-Classics)
(August 30, 2005)
Language: English
ISBN-10: 0143036157

Editorial Reviews
The Times Literary Supplement
[Skidelsky] places Keynes where he belongs, at the heart of twentieth- century British history.
The definitive study of the most important economist of his time.
(Foreign Affairs)

This book is Skidelsky's one volume abridged version of his previous three volume biography (1983, 1992, 2000) on J M Keynes. Skidelsky successfully weaves all of the different aspects and strands (personal, familial, historical, social, political, economic) of Keynes's life into a beautifully constructed historical tapestry that will keep the reader's attention from the first page to the last. All of the different talents Keynes possessed and displayed during his lifetime come alive on the pages of this book. Skidelsky is the master of his material as long as he concentrates on the vast nontechnical aspects of the life of his subject. Skidelsky has clearly mastered the historical and chronological events and interrelationships that occurred during Keynes's life. Unfortunately, Skidelsky does not have the necessary formal training in mathematics, logic, statistics or probability in order to properly understand or assess any of those parts of Keynes's scholarship that involves the use of formal logical and mathematical methods or analysis. These technical deficiencies in Skidelsky's academic training are the main defect, not only in this book but in the entire corpus of Skidelsky's writings on Keynes going back over 30 years.
I will concentrate on Skidelsky's error filled statements concerning Keynes's A Treatise on Probability (1921; TP) and the logical theory of probability. On p. 95, Skidelsky conflates the principle of indifference (poi) with the principle of insufficient reason. They are not the same. Keynes's poi requires a balance or symmetry of the relevant, available evidence or factors involved before equiprobabilities are assigned. The poi can't be applied if there is no relevant evidence. Advocates of the principle of insufficient reason, on the other hand, argue that equiprobabilities can be applied in states where no relevant evidence exists. Keynes always rejected this kind of reasoning. Skidelsky bases his assessment of Keynes's logical theory of probability on the error filled work of A. Carabelli and R. O'Donnell. Carabelli and O'Donnell base their assessments of the TP on four sources:1) Keynes's introductory guide to the measurement of probability in chapter III of the TP; 2) F. Ramsey's 1922 book review of the TP in The Cambridge Magazine; 3) F. Ramsey's 1926 book review of the TP in his article, "Truth and Probability", published in 1931 in a book of articles; and 4) Keynes's 4 page eulogy and very brief review of the book in 1931. In chapter III, Keynes had already made it clear to the alert reader, who had a mind of his/her own (and would not ape the preposterous , nonsensical claims made by F. Ramsey that by nonnumerical and nonmeasurable Keynes meant that numbers could not be used in general to estimate probabilities, i. e. , that Keynesian probabilities were like a surveyor assigning nonnumerical heights to a mountain hidden in the mist) that the vast majority of Keynesian probabilities used in common discourse were/are interval estimates. John Maynard Keynes is the originator and founder of the interval estimate approach to probability. Keynes spells it out in a number of places in the TP:"... we judge that the probability of the actual argument lies between these two (numbers; reviewers note). Since our standards, therefore, are referred to numerical measures in many cases where actual measurement is impossible, and since the probability lies BETWEEN (Keynes's emphasis) two numerical measures... " (1921, p. 32). After warning the reader not to reach any conclusions based on chapter III alone until after Part II of the TP was reached (p. 37) , Keynes gives his definition of nonnumerical in chapter 15 of Part II on p. 160 of the TP. On pp. 161-163 and pp. 186-194 (ch. 17) , Keynes presents his approximation approach. It has nothing to do with ordinal rankings (see Skidelsky's queer claims on pp. 284-285, for instance). An upper bound and a lower bound are specified for some 13 worked out probability problems. One of these problems (a revision of Boole's problem 10) is then made the foundation for Part III of the TP. Part III is then made the logical foundation for Part V. Carabelli's and O'Donnell's "reading" of Keynes's TP is very poor, at best. Skidelsky's conclusions, based on their very poor reading, are very poor. Skidelsky also appears to have been misled by Richard Kahn and Joan Robinson into believing that Keynes was a strictly literary economist, who was a poor mathematician by 1927. Supposedly, Keynes had never taken the twenty minutes that was necessary to understand the theory of value (microeconomics). Based on these bizarre beliefs, Skidelsky comes to the queer conclusion that Keynes deliberately refused to present any formal mathematical model of his general theory in the General Theory (1936; GT). Any mathematically trained reader can find Keynes's completely worked out model, with the results presented in the form of elasticities so that a reader of the GT can compare Keynes's results with those of A C Pigou, in chapters 19, 20, and 21 of the GT. Keynes then compares and contrasts his model with Pigou's model, who had also presented his results in the form of elasticities, in the appendix to chapter 19 of the GT. A technically trained economist should purchase a copy of the GT instead of this book.

Anyone who has taken a course in macroeconomics knows who Keynes is. Economics is full of camps, conflicting doctrines, feuds, rivalries, etc. Keynes was unique in that, unlike other economists who are indoctrinated or are in love with a theory, he was never scared of giving up an idea that did not work. If one was to read his "Tract on Monetary Reform" one might be fooled into thinking that it was Milton Friedman that was writing and not the J. M Keynes who revolutionized economic thought with his General Theory. This pragmatism is what sets Keynes apart from every other economist. But why Keynes was so different from others is something students never learn.
This biography does an admirable job of tracing Keynes' upbringing, his education, career, and contributions in the light of circumstances that Keynes lived through and shaped his ideas. It is also full of nuggets about Keynes' idiosyncracies which humanizes the biography and shows the real person behind the aura. The book is long, but 63 years of action-packed life requires such detail. The Chinese say, May we live in interesting times. Keynes certainly lived in interesting times with the result that this book is just as interesting.