Introduction

Abstract

The expression philosophical logic gets used in a number of ways. On one approach it applies to work in logic, though work which has applications in philosophy. On another, it is extended to include work in the philosophy of logic, including work on the semantics, metaphysics and epistemology of truth, logical truth and logical consequence, and work on the foundations of particular formal systems—including questions about what it is for something to be necessarily the case, or what a model is. Philosophical logic is also sometimes understood to include work in (and on the philosophy of) a broader class of formal systems, including game theory, decision theory, and probability calculi, and whatever else may be in view. We hereby decline to limit what counts as philosophical logic to any of these narrower conceptions: for the purposes of this volume philosophical logic is the study of logic—itself understood broadly—and its applications, pursued to philosophical ends.