Alex Rosenberg

Microeconomic theory and the theory of natural selection share salient features. This has encouraged economics to appeal to the character of evolutionary theory in defending the adequacy of microeconomics, despite its evident weaknesses as an explanatory or predictive theory. This paper explores the differences and similarities between these two theories and the phenomena they treat in order to assess the force of the economist's appeal to evolutionary theory as a model for how economic theory should proceed.

Is life a purely physical process? What is human nature? Which of our traits is essential to us? In this volume, Daniel McShea and Alex Rosenberg – a biologist and a philosopher, respectively – join forces to create a new gateway to the philosophy of biology; making the major issues accessible and relevant to biologists and philosophers alike. Exploring concepts such as supervenience; the controversies about genocentrism and genetic determinism; and the debate about major transitions central to contemporary thinking about macroevolution; the authors lay out the broad terms in which we should assess the impact of biology on human capacities, social institutions and ethical values.

It is argued that the assessment of the strength of the evidence for the Darwinian theory of evolution by natural selection offered by Michael Ruse in the Philosophy of Biology is in one respect too weak and in the other too strong. His claim that artificial selection provides at best analogical evidence for the theory is shown to rest on a spurious distinction between artificial and natural selection. His argument that Darwinian theory, unlike its competitors, accounts for the cytological and genetic data is demonstrated to be unwarranted and fails to differentiate the actual degrees of evidential support provided by cytology and genetics for parts of differing and competing theories of evolution. The evidentially secure foundations of Darwin's theory are not challenged in this paper, only Ruse's account of their nature.

De gustibus non est disputandum. This maxim reflects a fundamental problem both for the study of markets and for the concern with morals. The problem is the intractability of tastes coupled with their indispensability for both positive and normative economics. Tastes are indispensable in positive microeconomic theory because, under the label ‘preferences,’ they, together with expectations, determine choice and behavior. Tastes are equally indispensable to welfare economics' conception of morally permissible arrangements, because these arrangements must reflect compromises between competing and conflicting preferences

In The Structure of Biological Science I argued that the theory of natural selection is a statistical theory for reasons much like those which makes thermodynamics a statistical theory. In particular, the theory claims that fitness differences are large enough and the life span of species long enough for increases in average fitness always to appear in the long run; and this claim, I held, is of the same form as the statistical version of the second law of thermodynamics.For the latter law also makes a claim about the long run, and its statistical character is due to this claim: thermodynamic systems must in the long run approach an equilibrium level of organization that maximizes entropy. Over finite times, given local boundary conditions, an isolated mechanical system, like the molecules in a container of gas, may sometimes interact so as to move the entropy of the system further from, instead of closer to the equilbrium level. But given enough interacting bodies, and enough time, the system will always eventually move in the direction prescribed by the law. Thus, we can attach much higher probabilities to the prediction that non-equilibrium systems will reflect greater entropy in future periods than we can to predictions that they will move in the opposite direction. And as we increase the amount of time and the number of bodies interacting, the strength of the probability we can attach to the prediction becomes greater and greater.

The discussion of Darwinism's past--of what Charles Darwin wrote and thought--is crucial to an understanding of the history and philosophy of biology, but largely irrelevant to assessing its current warrant and its future prospects. In this paper the structure, and the credibility of the theory are defended against a variety of criticisms both of biologists and anti-Darwinians. It is argued that many features of the theory often treated as defects, like its generality and neutrality, its openness to realization at many levels of organization, its lack of specific predictive content, and its anomalous relation to taxonomy, are in fact important strengths that any theory with the range and bearing of the theory of natural selection must have. These strengths are specifically related, in the latter portion of the paper, to the evolutionary discoveries we can expect from the revolutionary developments in molecular biology.

Defiendo la legitimidad de la pregunta acerca de cuál puede ser el estatuto cognitivo de la Teoría Económica, y sostengo que la Teoría se comprende mejor como una rama de la Filosofía Política formal, en concreto, como una especie de contractualismo. Esto parece particularmente adecuado corno explicación de la Teoría deI equilibrio general. Dado el carácter intencional de las variables explicativas de la Teoría Económica y el papel de la información al realizar una elección, se argumenta que es improbable que dicha Teoría pueda garantizar el poder predictivo, que le permitiría funcionar corno teoría factual en vez de corno teoría normativa.I defend the integrity of the question of what the cognitive status of economic theory could amount to, and I argue that the theory is best understood as a compartment of formal political philosophy, in particular a species of contractarianism. This seems particularly apt as an account of general equilibrium theory. Given the intentional character of the explanatory variables of economic theory and the role of information in effecting choice, it is argued that economic theory is unlikely to secure the predictive power that would enable it to function as a factual instead of a normative theory.