Unrestricted Logical Inferentialism

This chapter develops and defends an unrestricted inferentialist theory of the meanings of logical constants. Unlike restricted inferentialism, unrestricted inferentialism puts no constraints on which rules can determine meanings. The foundations of inferentialism are also discussed, including various types of holism and the distinction between basic and derivative rules. In order to develop and defend a detailed inferentialist theory of logic, this chapter provides an inferentialist account of the “logical” constants, solves Carnap’s categoricity problem for the meanings of logical constants, and provides inferentialist approaches to both the psychology and metaphysics of logic. Finally, the chapter briefly discusses the challenge to unrestricted inferentialism posed by tonk and related types of bad company. Building on the foundation provided by Part I (chapters 1-2) of the book, this chapter provides a freestanding development and defense of logical inferentialism.

Equivalence

What is it for theories to be equivalent? Two extreme accounts are considered. According to the account I defend, equivalent theories are those that say the same thing at the fundamental level. This leads to certain uncomfortable choices: should a theory of time be based on a fundamental relation of earlier-than, or later-than? Should a metaphysics of logic including negation include also conjunction, or disjunction? These are normally regarded as paradigmatically equivalent theories, but my account cannot recognize this. According to the second extreme account, relations of equivalence need not be underwritten by a fundamental account of their common content. We can "quotient out" theoretical differences by simply saying, without explaining, that theories are equivalent. Objections are given to this account. But the more important moral is that the issue of quotienting often lies under the surface, but has profound implications across metaphysics and philosophy of physics, including the discussions of structuralism in earlier chapters.

Elliot D. Cohen on the Metaphysics of Logic-Based Therapy

In this essay I consider the question of whether Elliot D. Cohen has justified sufficiently the metaphysical basis for his Logic-Based Therapy as presented in his paper on “The Metaphysics of Logic-Based Therapy (IJPP, this issue). Although Cohen discusses four different foundations of his cognitive theory, I focus only on one. It is the most important basis of his theory, viz., that human beings logically deduce the cognitive-behavior com­ponents of their emotions from premises. First, I question Cohen’s analysis of the emotion rules we use to deduce evaluations of actions from. Second, I challenge Cohen’s view that we deduce our evaluations from emotion rules. Although I do not think my challenges completely undermine Cohen’s theory, they do raise serious concerns for a theory faced with a preponderance of causal therapies.

The Metaphysics of Logic-Based Therapy

This article examines four key metaphysical assumptions of LBT regarding human emotions, human fallibility, reality, and human freedom. By way of examining these assumptions it shows how the theory of LBT systematically integrates philosophy and logic into a cognitive-behavioral approach to philosophical practice.