Stephen Schiffer

Suppose we think in a language of thought. Then Paul Boghossian' is prepared to argue, first, that there may be ambiguous Mentalese expression types that have unambiguous tokens, and, second, that the way in which this is possible allows for otherwise valid theoretical or practical reasoning to be rendered invalid owing to equivocation of a sort that may be undetectable to the reasoner. Paul sees this as a possible basis from which to launch an argument for what some might call "narrow content", and this is a question I'll take up later

In this foundational work on the theory of linguistic and mental representation, Stephen Schiffer surveys all the leading theories of meaning and content in the philosophy of language and finds them lacking. He concludes that there can be no correct, positive philosophical theory or linguistic or mental representation and, accordingly advocates the deflationary "no-theory theory of meaning and content." Along the way he takes up functionalism, the nature of propositions and their suitability as contents, the language of thought and other sententialist theories of belief, intention based semantics, and related issues in ontology. Stephen Schiffer is Professor of Philosophy at the City University of New York Graduate Center. A Bradford Book.

SI is a paradox because it presents four appearances that cannot all be veridical: first, it appears to be valid—after all, it’s both classically and intuitionistically valid; second, its sorites premiss, (2), seems merely to state the obvious fact that in the sorites march from 2¢ to 5,000,000,000¢ there is no precise point that marks the cutoff between not being rich and being rich; third, premiss (1), which asserts that a person with only 2¢ isn’t rich, is surely true; and fourth, the conclusion (3), which asserts that a person with 5,000,000,000¢—i.e. $50 million—isn’t rich, is surely false.

In The Things We Mean I argue that there exist such things as the things we mean and believe, and that they are what I call pleonastic propositions. The first two chapters offer an initial motivation and articulation of the theory of pleonastic propositions, and of pleonastic entities generally. The remaining six chapters bring that theory to bear on issues in the theory of content: the existence and nature of meanings; knowledge of meaning; the meaning relation and compositional semantics; the relation between content-involving facts and underlying physical facts; vagueness and indeterminacy; conditionals; normative discourse; and the role of propositional content in explanation, prediction, and knowledge acquisition.

Philosophers have long debated whether abstract objects such as numbers and properties exist, but in recent years philosophical debate about what things exist has been ratcheted up more than a notch to question whether even ordinary objects such as pineapples and tables exist. One view has it that all existence questions are difficult questions whose answers hang on achieving an ontological theory that succeeds in carving nature at its joints. Some proponents of this view further claim to have succeeded in that carving, even without the benefit of any instrument sharper than the a priori arguments conjured in their armchairs, and to have discovered, alas, that no ordinary concrete objects exist. Naturally, many of us have been made to wonder what premise in the argument for that conclusion enjoys a plausibility greater than that of the negation of the argument's conclusion. In her remarkable new book, Ontology Made Easy, Amie Thomasson strives to do much more than that in defense of common‐sense ontology. But not only for common‐sense ontology. She propounds a unified approach to all existence questions—whether about the existence of dogs, shoes or tables, or about the existence of numbers, propositions or fictional characters—according to which existence questions “are not deep and difficult subjects for metaphysical dispute, but rather questions to be resolved straightforwardly by employing our conceptual competence, often combining this with empirical investigations” (20). Thomasson calls her way of resolving existence questions the easy approach to ontology, and to that I now turn.

Pleonastic entities are entities whose existence is secured by something-from-nothing transformations, these being conceptually valid inferences that take one from a statement in which no reference is made to a thing of a certain kind to a statement—often a pleonastic equivalent of the first statement—in which there is a reference to a thing of that kind. The possibility of pleonastic entities is further explained in terms of the notion of one theory being a conservative extension of another. Propositions are pleonastic entities, and the way in which they are individuated shows how pleonastic propositions are both fine-grained and unstructured.

I’m going to argue for something that some of you will find repugnant but which I can’t help thinking may be true—namely, that there are no determinate moral truths. As will become apparent, my interest in moral discourse as manifested in this paper derives more than a little from my interest in the theory of meaning. Moral discourse has always presented a puzzle for the theory of meaning and philosophical logic, and I take myself to be following the advice of Bertrand Russell when he recommended testing philosophical theories by their capacity to deal with puzzles, “since these serve much the same purpose as is served by experiments in physical science.” Section (1) offers an epistemological argument for the claim that there are no determinate moral truths. This argument raises further questions, which subsequent sections try to answer. In the course of answering those further questions, another, non-epistemological, argument is offered for the claim that there are no determinate moral truths. In the end, I hope we see not only that there are no determinately true moral propositions, but what it is about moral concepts which makes that so

When I was invited to participate in this symposium, I welcomed what I thought would be the opportunity to apply my views about the semantics and logic of vague language to the real-life problems of vagueness legal theorists worry about. I confess to having formed my ambition without a very clear sense of what jurisprudential problems might be illuminated by general theories of vagueness. To be sure, I was able to guess that a symposium on Vagueness and Law must have something to do with the dilemmas courts face when it is indeterminate how a legal dispute should be resolved. What I had not thought through was how philosophers like myself might help to illuminate those dilemmas by bringing to bear on them their own logico-semantical theories of vagueness. This was unfortunate because, having done a bit of homework, I have reached the conclusion that philosophical theories of vagueness, even if true, have nothing to offer jurisprudential concerns about vagueness. Once she is reminded of certain platitudes about vagueness, the legal theorist needs no further help from philosophers of language and logic. Let’s see why this is so