This is a paperback edition of a major contribution to the field, first published in hard covers in 1977. The book outlines a general theory of rational behaviour consisting of individual decision theory, ethics, and game theory as its main branches. Decision theory deals with a rational pursuit of individual utility; ethics with a rational pursuit of the common interests of society; and game theory with an interaction of two or more rational individuals, each pursuing his own interests in a (...) rational manner. (shrink)

The purpose of this paper is to show how some of the controversial questions concerning utilitarianism can be clarified by the modelling techniques and the other analytical tools of decision theory (and, sometimes, of game theory). It is suggested that the moral rules of utilitarian ethics have a logical status similar to that of the normative rules (theorems) of such formal normative disciplines as decision theory and game theory.The paper argues that social utility should be defined, not in hedonistic or (...) in ideal-utilitarian terms, but rather in terms of individual preferences, in accordance with the author's equiprobability model of moral value judgments. (shrink)

It is argued that we need a richer version of Bayesian decision theory, admitting both subjective and objective probabilities and providing rational criteria for choice of our prior probabilities. We also need a theory of tentative acceptance of empirical hypotheses. There is a discussion of subjective and of objective probabilities and of the relationship between them, as well as a discussion of the criteria used in choosing our prior probabilities, such as the principles of indifference and of maximum entropy, and (...) the simplicity ranking of alternative hypotheses. (shrink)

The paper first summarizes the author's decision-theoretical model of moral behavior, in order to compare the moral implications of the act-utilitarian and of the rule-utilitarian versions of utilitarian theory. This model is then applied to three voting examples. It is argued that the moral behavior of act-utilitarian individuals will have the nature of a noncooperative game, played in the extensive mode, and involving action-by-action maximization of social utility by each player. In contrast, the moral behavior of rule-utilitarian individuals will have (...) the nature of a cooperative game, played in the normal mode, and involving a firm commitment by each player to a specific moral strategy (viz. to the strategy selected by the rule-utilitarian choice criterion) — even if some individual actions prescribed by this strategy, when considered in isolation, should fail to maximize social utility. The most important advantage that rule utilitarianism as an ethical theory has over act utilitarianism lies in its ability to give full recognition to the moral and social importance of individual rights and personal obligations. It is easy to verify that action-by-action maximization of social utility, as required by act utilitarianism, would destroy these rights and obligations. In contrast, rule utilitarianism can fully recognize the moral validity of these rights and obligations precisely because of its commitment to an overall moral strategy, independent of action-by-action social-utility maximization. The paper ends with a discussion of the voter's paradox problem. The conventional theory of rational behavior cannot avoid the paradoxical conclusion that, in any large electorate, voting is always an irrational activity because one's own individual vote is extremely unlikely to make any difference to the outcome of any election. But it can be shown that, by using the principles of rule-utilitarian theory, this paradox can easily be resolved and that, in actual fact, voting, even in large electorates, may be perfectly rational action. More generally, the example of rule utilitarianism shows what an important role the concept of a rational commitment can play in the analysis of rational behavior. (shrink)

Utilitarianism and the Concept of Social UtilityIn this paper I propose to discuss the concepts ofequalityandjusticefrom a rule utilitarian point of view, after some comments on the rule utilitarian point of view itself.Let me start with the standard definitions.Act utilitarianismis the theory that a morally right action is one that in the existing situation will produce the highest expected social utility. (I am using the adjective “expected” in the sense of mathematical expectation.) In contrast,rule utilitarianismis the theory that a morally (...) right action is simply an action conforming to the correct moral rule applicable to the existing situation. The correct moral rule itself is that particular behavioral rule that would yield the highest expected social utility if it were followed by all morally motivated people in all similar situations. (shrink)

Philosophical errors are errors of a very peculiar nature.Obviously, errors occur in the different areas of science, as well as in everyday life. But these errors are sooner or later recognized and exposed, and – most importantly – once they are recognized and exposed, they are essentially rendered harmless, at least for those versed in the respective discipline. A false historical datum, an experimental error or a calculation mistake becomes indefensible as soon as it is noticed.

Ethics deals with two basic problems. One is what to do to have a good life from our own personal point of view, which I shall call the problem of personal wellbeing The other is what to do to have a good life from a moral point of view, which I shall call the problem of morality.

The publication in English of Karl R. Popper's The Logic of Scientific Discovery twenty-five years after the appearance of the German original, is an important event. At the time when many philosophers questioned the cognitive value of scientific hypotheses , Popper has shown how to reconcile the free use of bold explanatory hypotheses with an insistence on empirical testing. Many of Popper's views have now been accepted even by most of his earlier opponents, which is no small tribute to a (...) philosopher who had challenged an important current of opinion. But, though the basic aspects of Popper's theory have attracted considerable attention in recent years, some of his finer points have received insufficient discussion. It is hoped that the publication of this important book in English translation will now help to remedy this situation. (shrink)

Comentaré sólo la sección 2 de la contribución de Amartya Sen, donde discute un reciente artículo mío (Harsanyi, 1975).

When von Neumann's and Morgenstern's Theory of Games and Economic Behavior appeared in 1944, one thought that a complete theory of strategic social behavior had appeared out of nowhere. However, game theory has, to this very day, remained a fast-growing assemblage of models which have gradually been united in a new social theory - a theory that is far from being completed even after recent advances in game theory, as evidenced by the work of the three Nobel Prize winners, John (...) F. Nash, John C. Harsanyi, and Reinhard Selten. Two of them, Harsanyi and Selten, have contributed important articles to the present volume. This book leaves no doubt that the game-theoretical models are on the right track to becoming a respectable new theory, just like the great theories of the twentieth century originated from formerly separate models which merged in the course of decades. For social scientists, the age of great discover ies is not over. The recent advances of today's game theory surpass by far the results of traditional game theory. For example, modem game theory has a new empirical and social foundation, namely, societal experiences; this has changed its methods, its "rationality. " Morgenstern (I worked together with him for four years) dreamed of an encompassing theory of social behavior. With the inclusion of the concept of evolution in mathematical form, this dream will become true. Perhaps the new foundation will even lead to a new name, "conflict theory" instead of "game theory. (shrink)

It is argued that mathematical statements are "a posteriori synthetic" statements of a very special sort, To be called "structure-Analytic" statements. They follow logically from the axioms defining the mathematical structure they are describing--Provided that these axioms are "consistent". Yet, Consistency of these axioms is an empirical claim: it may be "empirically verifiable" by existence of a finite model, Or may have the nature of an "empirically falsifiable hypothesis" that no contradiction can be derived from the axioms.