Charles Sayward

One of the things C. D Broad argued many years ago is that certain 'scientific' arguments against dualist interactionism come back in the end to a metaphysical bias in favor of materialism. Here the authors pursue this basic strategy against another 'scientific' argument against dualism itself. The argument is called 'the argument from continuity'. According to this argument the fact that organisms and species develop by insensible gradations renders dualism implausible. The authors try to demonstrate that this argument fails to establish the implausibility of dualism.

We here establish two theorems which refute a pair of what we believe to be plausible assumptions about differences between objectual and substitutional quantification. The assumptions (roughly stated) are as follows: (1) there is at least one set d and denumerable first order language L such that d is the domain set of no interpretation of L in which objectual and substitutional quantification coincide. (2) There exist interpreted, denumerable, first order languages K with indenumerable domains such that substitutional quantification deviates from objectual quantification in K and this deviance remains for all name extensions I of K. We show these assumptions have actually been made, and then prove the refuting theorems.

Russell held that the theory of natural numbers could be derived from three primitive concepts: number, successor and zero. This leaves out multiplication and addition. Russell introduces these concepts by recursive definition. It is argued that this does not render addition or multiplication any less primitive than the other three. To this it might be replied that any recursive definition can be transformed into a complete or explicit definition with the help of a little set theory. But that is a point about set theory, not number theory. We have learned more about the distinction between logic and set theory than was known in Russell's day, especially as this affects logicist aspirations.

The force of sceptical inquiries into out knowledge of other people is a paradigm of the force that philosophical views can have. Sceptical views arise out of philosophical inquiries that are identical in all major respects with inquiries that we employ in ordinary cases. These inquiries employ perfectly mundane methods of making and assessing claims to know. This paper tries to show that these inquiries are conducted in cases that lack certain contextual ingredients found in ordinary cases. The paper concludes that these ordinary methods of inquiry, when employed in these limited cases, put us in a position in which we actually cannot know. Thus our ability to know will be a function of the added contextual elements that are found in ordinary cases. A second conclusion is that we come literally to observe bodily behaviour in the course of the sceptical inquiry; while in ordinary cases we observe pain-behaviour

An account of the logic of bivalent languages with truth-value gaps is given. This account is keyed to the use of tables introduced by S. C. Kleene. The account has two guiding ideas. First, that the bivalence property insures that the language satisfies classical logic. Second, that the general concepts of a valid sentence and an inconsistent sentence are, respectively, as sentences which are not false in any model and sentences which are not true in any model. What recommends this approach is (1) its relative simplicity, and (2) the fact that it leaves the fundamental features of classical logic intact.

The fundamental thought of moral relativism is set out as follows: moral criteria, derived from overall moral points of view, are used to derive particular moral judgments. Thus such a judgment might be correct relative to one overall moral point of view and incorrect relative to another. The evaluation of an overall moral point of view does not involve the application of moral criteria. Rather, the evaluation of a morality takes us outside the province of morality. The result of sharpening this view is a doctrine called system relativism. System relativism is contrasted with other conceptions of moral relativism that have recently been propounded. It is argued that system relativism is the most defensible version.

In this paper the authors recapitulate, justify, and defend against criticism the extension of the redundancy theory of truth to cover a wide range of uses of ‘true’ and ‘false’. In this they are guided by the work of A. N. Prior. They argue Prior was right about the scope and limits of the redundancy theory and that the line he drew between those uses of ‘true’ which are and are not susceptible to treatment via redundancy serves to distinguish two important and mutually irreducible types of truth: redundancy truth and predicative truth. Only the latter serves for semantic theorizing.

Robert cummins has recently attacked this line of argument: if p is a semantically primitive predicate of a first order language l, then p requires its own clause in the definition of satisfaction integral to a definition of truth of l. thus if l has infinitely many such p, the satisfaction clause cannot be completed and truth for l will remain undefined. against this cummins argues that a single clause in a general base theory for l can specify satisfaction conditions for even infinitely many semantically primitive predicates of l. against cummins we argue that a general base theory contains a primitive expression 'applies to' and that to make his case cummins would need to prove this expression stands for a semantical relation sufficient to a truth definition for l. not only is such a proof lacking but we show the claim to be altogether dubious

On the basis of observations J. J. C. Smart once made concerning the absurdity of sentences like 'The seat of the bed is hard', a plausible case can be made that there is little point to developing a theory of types, particularly one of the sort envisaged by Fred Sommers. The authors defend such theories against this objection by a partial elucidation of the distinctions between the concepts of spanning and predicability and between category mistakenness and absurdity in general. The argument suggests that further clarification of the concepts of spanning and category mistakenness should be sought in reflection upon the more familiar concepts of a sort of thing and a predicate category.

The significance of the semantical paradoxes for natural languages is examined. If Tarski’s reflections on the issue are correct, English is inconsistent. Paul Ziff responds to Tarskian reflections by arguing to the conclusion that no natural language is or can be inconsistent. The authors reject Ziff’s argument, but they defend something similar to its conclusion: no language, natural or otherwise, is or can be inconsistent in the way that Tarski holds languages capable of formulating the Epimenides are inconsistent.

Four views of arithmetical truth are distinguished: the classical view, the provability view, the extended provability view, the criterial view. The main problem with the first is the ontology it requires one to accept. Two anti-realist views are the two provability views. The first of these is judged to be preferable. However, it requires a non-trivial account of the provability of axioms. The criterial view is gotten from remarks Wittgenstein makes in Tractatus 6.2-6.22 . It is judged to be the best of four views. It is also defended against objections.

In this book a non-realist philosophy of mathematics is presented. Two ideas are essential to its conception. These ideas are (i) that pure mathematics--taken in isolation from the use of mathematical signs in empirical judgement--is an activity for which a formalist account is roughly correct, and (ii) that mathematical signs nonetheless have a sense, but only in and through belonging to a system of signs with empirical application. This conception is argued by the two authors and is critically discussed by three philosophers of mathematics.