For someone seeking to change the way economists perceive their world, there are two opposing strategies that can be followed. One is to emphasize the novelty of the theoretical schema being offered, showing how it leads to conclusions that contravene some important part of the accepted body of economics. This is the Keynesian strategy, as reflected in The General Theory. The alternative is to present the schema as though there were no intrinsic conflict between it and the prevailing doctrines, the new approach, it being suggested, simply serving to bring out some previously neglected points. This is the Marshallian strategy, as reflected in the Principles.

Neither strategy is without disadvantage. To stress the errors in economics as presently taught is to threaten the authority of the older generation of economists, thereby increasing their natural resistance to the new ideas. Since it is the older generation who determine what the younger generation will learn, this additional ground for hostility will hardly improve the chances of the new theoretical schema gaining acceptance. Yet to minimize the extent to which the new approach represents a discontinuity with past modes of thought is to run the risk that its significance will go unrecognized.

The present work wavers between the two strategies. On the one hand, it clearly seeks to supplant much of the existing body of microeconomic theory – or at least shrink it to the emphasis which it realistically deserves.