This is the first detailed study to explore the little-understood notions of "knowing who someone is," "knowing a person's identity," and related locutions. It locates these notions within the context of a general theory of believing and a semantical theory of belief- and knowledge-ascriptions.The books's main contention is that what one knows, when one knows who someone is, is not normally an identity in the numerical sense of "a = b," but rather a certain sort of predication to know who (...) someone is is just to know that that person is F, where "F" is a predicate that is "important," in a technical sense defined by the authors, for the purposes determined by context. Their book offers a rigorous formal semantics for ascriptions of knowing and of knowing-who in particular, solving such well-known problems and paradoxes as Kripke's Puzzle, and Quines difficulties with de re belief, along the way.The authors apply their analysis to each of several important issues in philosophy of language, philosophy of mind, and ethical theory in which the previously unexamined notion of "knowing who" has loomed large-the mechanics of linguistic referring, the foundations of epistemic logic, problems of self-knowledge and self-regarding belief, universalizability and "Golden Rule" arguments in ethics, and moral "personalism" versus "impartialism."Stephen Boër is Professor of Philosophy at the Ohio State University. William Lycan is Professor of Philosophy at the University of North Carolina and author of Logical Form in Natural Language. A Bradford Book. (shrink)

In this report I motivate and develop a type-free logic with predicate quantifiers within the general ontological framework of properties, relations, and propositions. In Part I, I present the major ideas of the system informally and discuss its philosophical significance, especially with regard to Russell's paradox. In Part II, I prove the soundness, consistency, and completeness of the logic.

I assume that the task of natural language semantics is to provide an unambiguous logical language into which natural language can be translated in such a way that the translating expressions display a structure which is isomorphic to the meaning of the translated expressions. Since language is a means of thinking and communicating mental contents, the meanings of singular terms cannot be the individuals of the substratist tradition, because such individuals are not cognizable entities. Thus I propose that the logical (...) language be based on Castaneda's guise theory, according to which singular terms always denote guises, i.e., roughly, bundles of properties. This, I argue, would result in a semantics which is in accordance with projects such as Lakoff's natural logic or Fodor's methodological solipsism. ;I first propose a formal system, GCC, which tries to be as faithful as possible to Castaneda's informal presentation of guise theory. It is therefore characterized by different forms of predication and a distinction between a level of property composition and a level of proposition composition. Such a distinction is dropped in a second system, GF, which presents a more traditional Fregean representation of predication. Yet, GF endorses essential assumptions of guise theory such as the existence of different sameness relations that can provide various interpretations for the English "is". I claim that GF provides more theoretical simplicity than GCC. ;Finally, I show the fruitfulness of the present approach by applying GF to a vast collection of linguistico-philosophical puzzles which includes but is not restricted to those that guise theory was originally designed to address: various versions of Frege's paradox, the paradox of analysis, Quine's puzzle on the number of planets, issues of reidentification and intentional identity, the anaphoric "it" of sentences such as "the lizard's tail fell off but then it grew back," problems connected with the use of "knowing-who ," proper names, indexicals and demonstratives. (shrink)