Philosophical logic

Philosophical logic, despite its name, is not a kind of logic, nor is it simply to be identified with the philosophy of logic. The philosophy of logic (or logics) is the philosophical examination of systems of formal logic and their applications and although this overlaps with philosophical logic in certain ways, the two fields of study are nonetheless distinct in their subject matter and methods. The subject matter of philosophical logic is, indeed, hard to define precisely, partly because it encroaches upon many other areas of philosophy�such as metaphysics, epistemology, the philosophy of mind and the philosophy of language�and partly because it is not immediately obvious what connects all the topics that philosophers have traditionally addressed under the heading of 'philosophical logic'. However, one quite appealing way to unify these topics under this heading is to describe philosophical logic as the philosophical elucidation of those notions that are indispensable for the proper characterisation of rational thought and its contents. The notions in question are ones like those of reference, predication, identity, truth, negation, quantification, existence, necessity, definition and entailment. These and related notions are needed in order to give adequate accounts of the structure of thoughts�particularly as expressed in language�and of the relationships in which thoughts stand both to one another and to objects and states of affairs in the world. However, it must be emphasized that philosophical logic is not really concerned with thought insofar as thought is a psychologicalprocess�that, rather, is the province of empirical psychology and the philosophy of mind�but only insofar as thoughts have contents which are evaluable as true or false. To conflate these two concerns is to fall into the error of psychologism, much decried by Gottlob Frege, arguably the founding father of modern philosophical logic. (For more information click here)

or handbook of philosophical logic