Carnap's new system of inductive logic

Abstract

During his life Carnap published two extensive, systematic works on inductive logic: Logical Foundations of Probability [4] and The Continuum of Inductive Methods [5]. These works report Carnap's research in induc tion and probability in the 1940's and early 1950's. After the publication of the Continuum in 1952 Carnap continued his research in inductive logic, and in the course of this research both his theory of inductive probability and his philosophy of induction underwent development. Most of Carnap's publications since 1952 have dealt with the philosophy and methodology of induction rather than inductive logic proper.1 A part of his recent research in inductive logic will be published in an extensive work 'The Basic System of Inductive Logic', forthcoming in Studies in Inductive Logic and Probability, I?II (edited by Rudolf Carnap and Richard Jeffrey).2 This paper discusses the development of Carnap's system of inductive logic and his philosophy of induction during the past twenty years. Our exposition and discussion of Carnap's inductive logic is based mainly on 'The Basic System of Inductive Logic' [13B-C] and partly on an earlier (unpublished) version of the same work, 'An Axiom System of Inductive Logic' [13A]. The theory presented in the 'Basic System' will be termed 'Carnap's New System' or the 'Basic System', and that presented in Log ical Foundations of Probability and the Continuum will be called 'Carnap's Old System'. Sections II?III of this paper discuss Carnap's philosophy of induction, Sections IV-VII contain an exposition of the main features of the 'Basic System', and the concluding Sections VIII-IX discuss the philosophical implications of Carnap's New System.