Logical possibility

Abstract: The purpose of this paper is to provide a partial logical analysis of a few concepts that may be classified as value concepts or as concepts that are closely related to value concepts. Among the concepts that will be considered are striving for, doing, believing, knowing, desiring, ability to do, obligation to do, and value for. Familiarity will be assumed with the concepts of logical necessity, logical possibility, and strict implication as formalized in standard systems of modal logic (such as S4), and with the concepts of obligation and permission as formalized in systems of deontic logic. It will also be assumed that quantifiers over propositions have been included in extensions of these systems.

Abstract: Ruth Millikan's extended argument for a biological view of the study of cognition in Language, Thought, and Other Biological Categories caught the attention of the philosophical community. Universally regarded as an important, even brilliant, work, its complexity and dense presentation made it difficult to plumb. This collection of essays serves both as an introduction to that much discussed volume and as an extension and application of Millikan's central and controversial themes, especially in the philosophy of psychology. The title essay, referring to the White Queen's practice of exercising her mind by believing impossible things, discusses meaning rationalism and argues that rationality is not in the head, indeed, that there is no legitimate interpretation under which logical possibility and necessity are known a priori. Nor are there any laws of rational psychology. Rationality is not a lawful occurrence but a biological norm that is effected in an integrated head-world system under biologically ideal conditions. In other essays, Millikan clarifies her views on the nature of mental representation, explores whether human thought is a product of natural selection, examines the nature of behavior as studied by the behavioral sciences, and discusses the issues of individualism in psychology, psychological explanation, indexicality in thought, what knowledge is, and the realism/antirealism debate.

Abstract: THE IDEA of possible worlds has both promised and, I believe, delivered understanding and insight in a wide range of topics. Pre-eminent here, I think, is the topic of broadly logical possibility, both de t the function of proper names and definite descriptions; the nature of counterfactuals; time and temporal relations; causal determinism; in philosophical theology, the ontological argument, theological determinism, and the problem of evil (see [7], chapters IV-X). In one respect, however, the idea of possible worlds may seem to have contributed less to clarity than to confusion; for if we take this idea seriously, we may find outselves committed to the dubious notion that there are or could have been things that do not exist. Let me explain.

Abstract: Much has been written about epistemological skepticism in the last ten or so years, but there remain some unanswered questions concerning the structure of what has become the canonical Cartesian skeptical argument. In this paper, I would like to take a closer look at this structure in order to determine just which epistemic principles are required by the argument. A standard way of presenting the argument is as follows. Let P be some arbitrary proposition about the external world, such as the proposition that I am now sitting. Let SK be some logically possible proposition which is incompatible with P-a skeptical counterpossibility to P-such as the proposition that I am a brain in a vat with sense experience qualitatively indistinguishable from my actual experience. Let us call the following argument A: