Harsanyi’s utilitarianism via linear programming

Contractarian Ethics and Harsanyi’s Two Justifications of Utilitarianism

Harsanyi defends utilitarianism by means of an axiomatic proof and by what he calls the ‘equiprobability model’. Both justifications of utilitarianism aim to show that utilitarian ethics can be derived from Bayesian rationality and some weak moral constraints on the reasoning of rational agents. I argue that, from the perspective of Bayesian agents, one of these constraints, the impersonality c...

Measurement-Theoretic Foundations of Preference Aggregation Logic for Weighted Utilitarianism

Harsanyi [4, 5] develops expected utility theory of von Neumann and Morgenstern [21] to provide two formalizations of utilitarianism. Weymark [22, 23] refers to these results as Harsanyi’s Aggregation and Impartial Observer Theorems. In this paper, we are concerned only with Aggregation Theorem. Sen [6] argues that von Neumann-Morgenstern expected utility theory is an ordinal theory and, theref...

Harsanyi’s ‘Utilitarian Theorem’ and Utilitarianism

A Reformulation of the Axiomatic Foundations of Relative Utilitarianism

We consider the aggregation of individual agents’ von Neumann-Morgenstern’s utility functions into a societal von Neumann-Morgenstern utility function. We start from Harsanyi’s [7] axiomatization of utilitarianism, and ask under which conditions a social preference order that satisfies Harsanyi’s axiom uniquely reveals society’s marginal rates of substitution between the probabilities of any tw...

Harsanyi’s Utilitarian Theorem: A Simpler Proof and Some Ethical Connotations

Harsanyi’s utilitarian theorem states that the social welfare function is the weighted sum of individuals’ utility functions if: (i) society maximizes expected social welfare; (ii) individuals maximize expected utility; (iii) society is indifferent between two probability distributions over social states whenever all individuals are. After giving a simpler proof, an alternative axiomatic founda...