Keynes on Probability, Expectations and Uncertainty

Abstract

The key to more profound and comprehensive understandings of Keynes’s thought is his philosophy. This is foundational to his thought in all other areas, especially to his economic theory, methodology, economic policy and politics. But for too long the illuminative power of this rich source of information has been neglected. Economists, imprisoned by narrow specialisation, have either been unaware of Keynes’s philosophy or have been held back by lack of philosophical skill. In attempting to comprehend Keynes ‘the economist’ they have failed adequately to investigate Keynes ‘the philosopher’. Philosophers, for their part, have been well aware of his Treatise on Probability but have used it solely for philosophical purposes, showing little interest in its relations to other areas of his thought. Fortunately, the situation has changed markedly over the last decade. In 1982 the first detailed study of Keynes’s philosophy and its links to his economics was completed,² and in the following years several further studies have appeared. That this Seminar is devoted to Keynes as ‘a philosopher-economist’ is an indication of the interest generated by this expanding and productive area of research.

I should like to thank the Australian Research Council for its assistance, and King’s College, Cambridge, and Professor David Papineau for permission to quote from the Keynes Papers. All references to Keynes’s published writings are to the Collected Writings of John Maynard Keynes, the reference taking the form of the. abbreviation CW, followed by the volume number in italics and the page number(s).