Abstract

This chapter concerns with rational preferences in the face of uncertainty. The goodness of uncertain prospects is best understood in terms of rational preferences. The chapter discusses some necessary spadework. Its particular purpose is to defend some parts of expected utility theory as an account of rational preferences. It explains the general idea of expected utility theory, and particularly how it is founded on axioms. The principal axiom is also explained. It is often called the 'sure‐thing principle', and it amounts to an assumption of strong separability. The chapter further aims to develop an argument about individuation in the context of a simpler axiom, namely transitivity. It extends the argument to the sure‐thing principle and then discusses a threat to another of the axioms of expected utility theory, which is raised by author's defence of the sure‐thing principle.