What distinguishes preference utilitarianism (PU) from other utilitarian positions is the axiological component: the view concerning what is intrinsically valuable. According to PU, intrinsic value is based on preferences. Intrinsically valuable states are connected to our preferences (wants, desires) being satisfied.

Deliberation about what to do in any context requires reasoning about what will or would happen in various alternative situations, including situations that the agent knows will never in fact be realized. In contexts that involve two or more agents who have to take account of each others' deliberation, the counterfactual reasoning may become quite complex. When I deliberate, I have to consider not only what the causal effects would be of alternative choices that I might make, but also what other agents might believe about the potential effects of my choices, and how their alternative possible actions might affect my beliefs. Counterfactual possibilities are implicit in the models that game theorists and decision theorists have developed – in the alternative branches in the trees that model extensive form games and the different cells of the matrices of strategic form representations – but much of the reasoning about those possibilities remains in the informal commentary on and motivation for the models developed. Puzzlement is sometimes expressed by game theorists about the relevance of what happens in a game ‘off the equilibrium path’: of what would happen if what is (according to the theory) both true and known by the players to be true were instead false.

In this article, I shall suggest an approach to the justification of normative moral principles which leads, I think, to utilitarianism. The approach is based on asking what moral norms we would each endorse if we had no prior moral commitments. I argue that we would endorse norms that lead to the satisfaction of all our nonmoral values or goals. The same approach leads to a view of utility as consisting of those goals that we would want satisfied. In the second half of the article, I examine the implication of this view for several issues about the nature of utility, such as the use of past and future goals. The argument for utilitarianism is not completed here. The rest of it requires a defense of expected-utility theory, of interpersonal comparison, and of equal consideration (see Baron, 1993; Broome, 1991).

Jon Elster reports that in 1940, and again in 1970, the U.S. draft lottery was challenged for falling short of the legally mandated ‘random selection’ (1989, pp. 45–6). On both occasions, the physical mixing of the lots appeared to be incomplete, since the birth dates were clustered in a way that would have been extremely unlikely if the lots were fully mixed. There appears to have been no suspicion on either occasion that the deficiency in the mixing was intended, known, or believed to favor or disfavor any identifiable group. If the selection was non-random in the way charged, Elster asks, was it unfair?

More than many other Austrians, Mises tried to found aprioristic methodology on a well defined and developed epistemology. Although references to Kant are scattered rather unsystematically throughout his works, he nevertheless used an unequivocal Kantian terminology. He explicitly defended the existence of ‘a priori knowledge’, ‘synthetic a priori propositions’, ‘the category of action’, and so forth.

Professor Hausman has written an interesting and instructive book. Though I am by no means favourably disposed to methodology for economists, (its results seem to have been pretty disastrous), I found reading Hausman enjoyable and I came away having learned things worth learning. But not all is well, largely because Hausman is a philosopher first and an economist a poor second. There are also important questions where one would have expected philosophic help which are not asked at all.

The most important analytical tool in non-cooperative game theory is the concept of a Nash equilibrium, which is a collection of possibly mixed strategies, one for each player, with the property that each player's strategy is a best reply to the strategies of the other players. If we do not go into normative game theory, which concerns itself with the recommendation of strategies, and focus instead entirely on the positive theory of prediction, two alternative interpretations of the Nash equilibrium concept are predominantly available.

In the more traditional one, a Nash equilibrium is a prediction of actual play. A game may not have a Nash equilibrium in pure strategies, and a mixed strategy equilibrium may be difficult to incorporate into this interpretation if it involves the idea of actual randomization over equally good pure strategies. In another interpretation originating from Harsanyi (1973a), see also Rubinstein (1991), and Aumann and Brandenburger (1991), a Nash equilibrium is a ‘consistent’ collection of probabilistic expectations, conjectures, on the players. It is consistent in the sense that for each player each pure strategy, which has positive probability according to the conjecture about that player, is indeed a best reply to the conjectures about others.

1. Despite the plain fact that there is nothing in this world that can be proved without reliance on some assumption or another (perhaps only the assumption that the laws of logic are correct), there is an inalienable difference between an argument that begins by assuming what it is designed to establish and one that begins by assuming the contradictory of what it is designed to establish. Arguments of the first kind are uncontroversially acknowledged to be circular, or question-begging; though valid they achieve nothing. Those of the second kind conform to the classical pattern of reductio ad absurdum or indirect proof. A typical example is the proof of the irrationality of √2, which begins by assuming that for some integral m, n the identity m2/n2 = 2, and (using some trite principles of number theory) arrives at a contradiction. Nothing whatever is established or justified by arguments of the first kind, even granted the truth of all the other assumptions (if any), and the validity of the rules of inference; while the second may establish that, if those assumptions are true (and the rules of inference employed valid), then the additional assumption (that √2 is rational) is false.

The Inexact and Separate Science of Economics (ISSE) offers an overview of standard microeconomics and general equilibrium theory. These are not the whole of orthodox economics, and orthodox economics is not the whole of economics. But orthodox economics dominates the profession, and the theoretical core of microeconomics and general equilibrium theory – what I called ‘equilibrium theory’ – is central to most orthodox economics. Unlike many methodological works, which focus almost exclusively on the empirical problems of equilibrium theory and its applications, ISSE is also concerned with the structure, strategy and heuristics of equilibrium theorizing, and it attempts to link questions about theory appraisal to questions about structure and strategy. It is addressed both to philosophers interested in epistemological questions posed by the social sciences and to economists interested in reflecting on and improving their discipline. Its inspiration lies in the work of John Stuart Mill.