ABSTRACT
The classical theories of rational choice under risk and uncertainty, as exemplified by the systems of Ramsey, von Neumann and Morgenstern, Savage and Jeffrey, give the impression of being largely self-contained. Another science—evolutionary biology—has also entered the decision-theoretic scene to the extent that the biological adaptiveness of particular patterns of choice behavior is sometimes discussed. To judge intelligently whether a genuine reduction of decision theory to biology might be possible, it is necessary to examine the details of a typical piece of decision theoretically interpretable evolutionary reasoning. Clearly, there is a close formal analogy between a conventional biological analysis which seeks to predict or explain organismic behavior, and traditional decision-theoretic methods intended to characterize rational behavior. Biologists assert that organisms, humans presumably included, tend to possess those behaviors which maximize their fitness. There are at least three ways to interpret the assertion that decision theory is reducible to evolutionary biology.
