Keynes's A Treatise on Probability is based on Boole's formal, mathematical, symbolic logic: Keynes was a formalist and logicist

Abstract

J M Keynes’s work in his A Treatise on Probability (1921) is based on the formal application of Boole’s relational, propositional logic and interval valued probability as presented in his The Laws of Thought (1854). Keynes then based his A Treatise on Money and General Theory on his work in Part II of the A Treatise on Probability as presented in Chapters X through XVII. This work is the basis for Keynes’s comments on mathematical and statistical methods and application in chapters 6,7 and 8 of Volume I of his 1930 A Treatise on Money and chapters 4 ,12 and 17 of the General Theory  on  using approximation, inexact measurement and  reasonable calculation as opposed to precise ,exact, unreasonable mathematical expectations.

Keynes’s clear statements in his Treatise on Probability about the nature of his technical work can only lead to the following conclusion -Keynes was a formalist and a logicist .All existing orthodox and heterodox “interpretations” of Keynes’s works  are attempts by economists to reinterpret Keynes’s work ,so as to try to  fit him into some version of  either Benthamite utilitarianism  (precise probability and precise utility a la James Tobin,1958) or a nihilist position(Joan Robinson ,G L S Shackle ,T. Lawson ,Post Keynesians ,Institutionalists).

Keynes’s position is so clearly defined and presented by him in his A Treatise on Probability that the only conclusion possible is that both orthodox and heterodox economists have  never  read Keynes’s A Treatise on Probability ,except possibly for small , scattered bits and pieces cobbled together in a confused and confusing manner .The justification for this decision not to read the A treatise on Probability  is based on the false   claim that F P Ramsey had shown that Keynes’s formal, Boolean, relational , propositional logic was erroneous .Accepting Ramsey’s false  claims   thus made  it impossible for economists to see  that the underlying  foundations of the A Treatise on Money and  General Theory  are built on the formal ,mathematical analysis presented in  Part II of Keynes’s A treatise on Probability.

Keynes later extended his propositional logic to include an introductory use of predicate (1st order) logic as defined on p.56 and applied in chapter 33 of the A Treatise on Probability on pp.405-425.

Keywords: Boolean relational, propositional logic; mathematical, formal, symbolic logic; objective, logical, probability relation; related versus unrelated propositions.