The General Theory of Second Best

There is an important basic similarity underlying a number of recent works in apparently widely separated fields of economic theory. Upon examination, it would appear that the authors have been rediscovering, in some of the many guises given it by various specific problems, a single general theorem. This theorem forms the core of what may be called The General Theory of Second Best. Although the main principles of the theory of second best have undoubtedly gained wide acceptance, no general statement of them seems to exist. Furthermore, the principles often seem to be forgotten in the context of specific problems and, when they are rediscovered and stated in the form pertinent to some problem, this seems to evoke expressions of surprise and doubt rather than of immediate agreement and satisfaction at the discovery of yet another application of the already accepted generalizations.