In response to the question in the title, Does Altruism Exist?, David Sloan Wilson argues forcefully that altruism exists and that the biological mechanism of group selection is responsible. He argues that group selection should be taken especially seriously for humans, since cultural evolution is especially important for us. Economists' view of basic human motivations should then include altruism. Wilson promotes a strong form of pervasive altruism, which seems bound to be inconsistent with many economic phenomena. Although a moderate version of the position he advocates is not easily dismissed, it is unclear what such an extended theory would look like. (JEL D64, Z13)

This paper first considers the implications of biological evolution for economic preferences. It analyzes why utility functions evolved, considers evidence that utility is both hedonic and adaptive, and suggests why such adaptation might have evolved. Time preference and attitudes to risk are treated—in particular, whether the former is exponential and the latter are selfish. Arguments for another form of interdependence—a concern with status—are treated. The paper then considers the evolution of rationality. One hypothesis examined is that human intelligence and longevity were forged by hunter-gatherer economies; another is that intelligence was spurred by competitive social interactions.

This paper supposes an individual cares about his/her own wealth not only directly but also via the relative standing that this wealth induces. The implications for risk-taking are investigated in particular. Such a model provides a natural explanation of the "concave-convex-concave" utility described by M. Friedman and L. Savage (1948). However, there are a number of key differences between the present model and any model based on own wealth alone. For example, an equilibrium wealth distribution here may have a middle class. Further, the status interaction involves an externality and an equilibrium wealth distribution may be Pareto inefficient. Copyright 1992 by The Econometric Society.

This paper advocates a generalized N-firm Stackelberg model as a plausible testable alternative description of oligopoly. A pure-strategy equilibrium must exist for this model. The main result is that efficiency obtains in the limit as the scale of each firm is shrunk relative to demand. This is demonstrated for the case of U-shaped average cost and also for that of natural monopoly. Copyright 1990 by American Economic Association.

This paper advocates a generalized N-firm Stackelberg model as a plausible testable alternative description of oligopoly. A pure-strategy equilibrium must exist for this model. The main result is that efficiency obtains in the limit as the scale of each firm is shrunk relative to demand. This is demonstrated for the case of U-shaped average cost and also for that of natural monopoly.

Consider the possible biological origin of the expected utility criterion. On the one hand, if individuals possess a utility function stemming from the rate of production of expected offspring, they can rapidly adapt to arbitrary unknown distributions in a bandit problem. Embedding such a utility function in a simple rule of thumb involving no beliefs about probabilities leads to evolutionary optimality. On the other hand, if any rule whatever yields evolutionary optimality for all distributions, this precise utility function must be implicit, in a revealed preference sense.

This paper studies endogenous risk-taking by embedding a concern for status (relative consumption) into an otherwise conventional model of economic growth. We prove that if the intertemporal production function is strictly concave, an equilibrium must converge to a unique steady state in which there is recurrent endogenous risk-taking. (The role played by concavity is clarified by considering a special case in which the production function is instead convex, in which there is no persistent risk-taking.) The steady state is fully characterized. It displays features that are consistent with the stylized facts that individuals both insure downside risk and gamble over upside risk, and it generates similar patterns of risk-taking and avoidance across environments with quite different overall wealth levels. Endogenous risk-taking here is generally Pareto-inefficient. A concern for status thus implies that persistent and inefficient risk-taking hinders the attainment of full equality.

We consider a growth model in which intergenerational transfers are made via stocks of private and public capital. Private capital is the outcome of individuals' private savings while decisions regarding public capital are made collectively. We hypothesize that private saving choices evolve through individual selection while public saving decisions are the result of group selection. The main result of the paper is that the equilibrium rate of return to private capital is at least 2–3 percent more than the rate of return to public capital. In other words, social choices involving intertemporal trade-offs exhibit much more patience than individual choices do. (JEL D11, D71, D91, H43)