Introduction

For John Harsanyi and John Rawls – as well as for Thomas Hobbes before them – the theory of the social contract is an application of the theory of rational decision. For Harsanyi and Rawls, it does not matter whether people are rational or whether there ever was or could have been a state of nature of the kind considered. The importance of the concepts rationality and the state of nature is not descriptive, but rather lies in the role that they play in a counterfactual definition of justice. A just arrangement is one to which rational decision makers would agree in the state of nature.

Justice is customarily depicted with a blindfold, a scale, and a sword. Both Harsanyi and Rawls structure the state of nature as the blindfold. Justice is rational decision behind the “veil of ignorance.” This is a departure from Hobbes. Rawls sees it as a Kantian approach, but justice had her blindfold long before Immanuel Kant formulated his categorical imperative.

There is a different tradition exemplified by David Hume. For Hume, the social contract is a tissue of conventions that have grown up over time. I cannot resist reproducing in full this marvelously insightful passage from his Treatise: