Commentary on Keynes' General Theory, part 1

On 13 December 1935, exactly 73 years ago to the day, John Maynard Keynes completed the preface to what was to become one of the most controversial and influential books of the 20th Century: The General Theory of Employment, Interest and Money.

Judging by the revival of interest in Keynesian economics that has come in the wake of the recent (and ongoing) global economic crisis, Keynes' General Theory looks set to become one of the most controversial and influential books of the 21st Century as well.

In his preface, Keynes notes that although his book "is chiefly addressed to [his] fellow economists", he "hope[s] that it will be intelligible to others."

This, then, marks the beginning of a detailed commentary on Keynes' General Theory by an interested non-economist.

Why undertake such a task?

There are three reasons.

First, the growing influence of The General Theory on current global economic policy. It is vital that we, economists and non-economists alike, have a clear understanding of Keynes' ideas. And more importantly, their implications.

Second, to the best of my knowledge, there is no such commentary available online.

And third, because you're worth it.

OK, that third reason is just some debris from the world of global cosmetics advertising that floated into my mind after I typed "And third". But it sounds good and three's a good number, so it stays.

The book consists of six main sections, or books as Keynes calls them:

Book I : Introduction

• Chapter 1: The General Theory
• Chapter 2: The Postulates of the Classical Economics
• Chapter 3: The Principle of Effective Demand
  

Book II: Definition and Ideas

• Chapter 4: The Choice of Units
• Chapter 5: Expectation as Determining Output and Employment
• Chapter 6: The Definition of Income, Saving and Investment
  Appendix on User Cost
• Chapter 7: The Meaning of Saving and Investment Further Considered

Book III: The Propensity to Consume

• Chapter 8: The Propensity to Consume: I. The Objective Factors
• Chapter 9: The Propensity to Consume: II. The Subjective Factors
• Chapter 10: The Marginal Propensity to Consume and the Multiplier

Book IV: The Inducement to Invest

• Chapter 11: The Marginal Efficiency of Capital
• Chapter 12: The State of Long-term Expectation
• Chapter 13: The General Theory of the Rate of Interest
• Chapter 14: The Classical Theory of the Rate of Interest
  Appendix on the Rate of Interest in Marshall’s Principles of Economics, Ricardo’s Principles of Political Economy and elsewhere
• Chapter 15: The Psychological and Business Incentives to Liquidity
• Chapter 16: Sundry Observations on the Nature of Capital
• Chapter 17: The Essential Properties of Interest and Money
• Chapter 18: The General Theory of Employment Re-stated

Book V: Money-Wages and Prices

• Chapter 19: Changes in Money-Wages
  Appendix on Prof. Pigou's Theory of Unemployment
• Chapter 20: The Employment Function
• Chapter 21: The Theory of Prices

Book VI: Short Notes Suggested by the General Theory

• Chapter 22: Notes on the Trade Cycle
• Chapter 23: Notes on Merchantilism, the Usury Laws, Stamped Money and Theories of Under-consumption
• Chapter 24: Concluding Notes on the Social Philosophy towards which the General Theory might lead

The entire book is available online here.

So much for introductory remarks.

Let's proceed to the Preface which begins as follows:

This book is chiefly addressed to my fellow economists. I hope that it will be intelligible to others. But its main purpose is to deal with difficult questions of theory, and only in the second place with the applications of this theory to practice. For if orthodox economics is at fault, the error is to be found not in the superstructure, which has been erected with great care for logical consistency, but in a lack of clearness and of generality in the premisses. Thus I cannot achieve my object of persuading economists to re-examine critically certain of their basic assumptions except by a highly abstract argument and also by much controversy.

We must note the following points:

• Whilst The General Theory is addressed primarily to economists, Keynes hopes that it will be intelligible to non-economists.
• The primary purpose of The General Theory is to deal with difficult theoretical issues and only secondarily with applications of this theory to practice.
• Keynes argues that the fault of orthodox economics (circa 1935) arises from its erroneous premisses and two characteristics of these premisses or basic assumptions in particular: their lack of clarity and generality.

Keynes ends his Preface much as he begins it:

The composition of this book has been for the author a long struggle of escape, and so must the reading of it be for most readers if the author’s assault upon them is to be successful,— a struggle of escape from habitual modes of thought and expression. The ideas which are here expressed so laboriously are extremely simple and should be obvious. The difficulty lies, not in the new ideas, but in escaping from the old ones, which ramify, for those brought up as most of us have been, into every corner of our minds.

We note that, according to Keynes: "The ideas which are here expressed so laboriously are extremely simple and should be obvious. The difficulty lies, not in the new ideas, but in escaping from the old ones". This suggests that, if anything, the non-economist may be better placed than the economist to judge The Classical Theory and its alternatives on their own merits, unencumbered by any professional prejudices.