Introduction

Abstract This is the introduction chapter of Confirmation Theory. Confirmation Theory is a book manuscript that Lewis wrote in 1969 on the basis of a course he’d given at UCLA. He submitted the manuscript to Harvard University Press who expressed an interest. It consists of seven chapters covering intensional semantics, probability measures, rational belief, principles of indifference and Carnap and Hintikka’s inductive systems. The work was intended to be accessible to students with, as Lewis put it, ‘hairy high-school algebra’. He described the manuscript to Richard Jeffrey as ‘Mathematically self-contained, with proofs for the major theorems’. Lewis originally envisaged that Carnap’s The Continuum of Inductive Methods (1952) be used as an accompanying text. Lewis focused on Carnap and Hintikka in particular because he believed that their work constituted the attractive core of what competing theories of confirmation had in common.