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In the preface to Logical Properties, McGinn writes: “The general theme of the book is a kind of realist anti-naturalism about logical properties. My tendency is to take logical notions at face value, rather than trying to reduce them to something else.” (p. vi) The five notions discussed in the book, each with its own chapter, are identity, existence, predication, necessity, and truth. McGinn’s anti-reductionism seems to me right for identity, existence, and predication. The case of truth, I think, is more complicated than McGinn allows because there are different notions of truth depending on what the truthmakers are taken to be, and how they are individuated; I won’t be discussing truth here. The case of necessity is where I have my sharpest disagreement with McGinn. I do not believe that necessity de re, which for McGinn is the central case, should be classified as logical at all: it is far too parochial and context-dependent for that. Necessity de dicto, on my view, may properly be classified as logical, but contra McGinn it is reducible to more fundamental logical notions.

In the Posterior Analytics (I 6, 75a18–27) Aristotle discusses a puzzle which endangers the possibility of inferring a non-necessary conclusion. His solution relies on the distinction between the necessity of the conclusion's being the case and the necessity of admitting the conclusion once one has admitted the premisses. The former is a factual necessity, whereas the latter is meant to be a normative or deontic necessity that is independent of the facts stated by the premisses and the conclusion. This paper maintains that Aristotle resorts to this distinction because he thinks that, as long as it is conceived as a factual relation, logical consequence cannot exist independently of the facts expressed by the premisses and the conclusion. As a corollary, the necessity of such a consequence relation always requires the necessity of these facts. Aristotle holds this factual conception of logical consequence responsible for the puzzle, since it cannot account for valid syllogisms with contingent or false premisses. The alternative conception of necessity is then introduced by him in order to make good this deficiency. The distinction between the necessity of being and the necessity of saying was revived by the Oxford logician E. W. B. Joseph, and taken over by Frank Ramsey in his seminal Truth and Probability, but has not received attention from recent interpreters of Aristotle's logic. This paper, however, argues that, in spite of its intrinsic interest, the distinction bore no significant fruit in Aristotle's logical doctrine.

The Lazy Argument, as it is preserved in historical testimonies, is not logically conclusive. In this form, it appears to have been proposed in favor of part-time fatalism (including past time fatalism). The argument assumes that free will assumption is unacceptable from the standpoint of the logical fatalist but plausible for some of the nonuniversal or part-time fatalists. There are indications that the layout of argument is not genuine, but taken over from a Megarian source and later transformed. The genuine form of the argument seems to be given in different form and far closer to Megarian logical fatalism and its purpose is not to defend laziness. If the historical argument has to lead to a logically satisfactory solution, some additional assumptions and additional tuning is needed.

Must we believe in logical necessity? I examine an argument for an affirmative answer given by Ian McFetridge in his posthumously published paper 'Logical Necessity: Some Issues', and explain why it fails, as it stands, to establish his conclusion. I contend, however, that McFetridge's argument can be effectively buttressed by drawing upon another argument aimed at establishing that we ought to believe that some propositions are logically necessary, given by Crispin Wright in his paper 'Inventing Logical necessity'. My contention is that Wright's argument, whilst it likewise fails, as it stands, to establish the necessity of necessity, established enough to close off what appears to me to be the only effective-looking sceptical response to McFetridge's original argument. My paper falls into four principal parts. In the first I expound McFetridge's argument and draw attention to the possibility of a certain type of sceptical counter to it. In the second, I begin a response to this sceptical move, taking it as far as I can without reliance upon argument of the kind given by Wright. Turning, then, to Wright's argument, I explain to what extent I think it is successful and seek to rebut some objections to the argument which, were they well-taken, would show that the argument cannot enjoy even the partial success I which to claim for it. Finally, I return to my main theme and try to show, with the assistance of what I take to be solidly established by Wright's argument, that the sceptical response collapses.

It is the aim of this paper to show that [the theological argument from Divine omniscience] is not more than a needlessly (and confusingly) elaborate version of the argument for fatalism discussed by Aristotle in de Interpretatione 9, which, since its sole premise is the Principle of Bivalence, may conveniently be called the logical argument for fatalism. If this is right, if the theological premisses of the theological argument can be shown to be strictly irrelevant to the fatalist conclusion, then it follows that it is pointless to try to avoid fatalism by modification of those theological premisses.

It is often remarked that Indian logic (IL) has no conception of necessity. But what kind of necessity is absent in this system? Logical necessity is presumably absent: the structure of the logical argument in IL is often given as a reason for this claim. However even a cursory understanding of IL illustrates an abiding attempt to formulate the idea of necessity. In Dharmakīrti's classification of inferences, one can detect the formal process of entailment in the inferences arising from class inclusion. In Western philosophy, Leibniz's invocation of 'contingent necessity' as distinguished from the 'necessary necessity' is part of a tradition that finds value in the idea of contingent necessity. In contemporary philosophy, this has been championed by Armstrong, specifically in the context of understanding the necessity inherent in scientific laws. In IL, the analysis of 'invariable concomitance' (vyāpti) is of crucial importance and its definitions are very complex. This paper argues how vyāpti can be understood in terms of contingent necessity and also how the complex definitions can be interpreted as an attempt to define contingent necessity in terms of 'logical' necessity.

Hume's arguments for the contention that causal necessity precludes logical necessity depend on the questionable principle that a cause must precede its effect. Hobbes' definition of entire cause, although it fails to account for causal priority, is not refuted by Hume. The objections of Myles Brand and Marshall Swain (Philosophical Studies, 1976) to my counterexample against Hume (Philosophical Studies, 1975) are ineffective. Their other objections to my criticisms of their argument against defining causation in terms of necessary and sufficient conditions (Synthese, 1970) are also mostly ineffective.

This paper is about the open future response to fatalistic arguments. I first present a typical fatalistic argument and then spell out the open future response as a response to that argument. Then I raise the question of how the open future response can be independently justified. I consider some possible ways in which the response might be defended, and I try to show that none of these is a plausible, non-question-begging defense. Next I formulate what I take to be the only plausible, nonquestion-begging defense of the open future response. This defense involves both (i) the claim that the laws of nature are indeterministic and (ii) a certain version of the correspondence theory of truth. Finally, I argue that there is a very surprising consequence of justifying the open future response by making the defense in question, namely, that the past is sometimes open. Fatalism is the view that whatever will happen in the future is inevitable, due to certain considerations about truth and time. Fatalism, in turn, is normally taken to imply that there is no such thing as genuine, human free will. Suppose that I am an anti-fatalist. Suppose I believe that Joe Montana is free to choose what he will have for lunch tomorrow, and suppose I take this case to be a paradigmatic example of one involving both evitability and human free will. Now suppose that I meet a fatalist, who presents the following argument.1..

In chapter 9 of De Interpretatione, Aristotle offers a defense of free will against the threat of fatalism. According to the traditional interpretation, Aristotle concedes the validity of the fatalist's arguments and then proceeds to reject the Principle of Bivalence in order to avoid the fatalist's conclusion. Assuming that the traditional interpretation is right on this point, it remains to be seen why Aristotle felt compelled to reject such an intuitive semantic principle rather than challenge the fatalist's inference from truth to necessity. The answer, I contend, lies in Aristotle's theory of truth and truthmakers.

This paper analyzes the logical truths as (very roughly) those truths that would still have been true under a certain range of counterfactual perturbations.What’s nice is that the relevant range is characterized without relying (overtly, at least) upon the notion of logical truth. This approach suggests a conception of necessity that explains what the different varieties of necessity (logical, physical, etc.) have in common, in virtue of which they are all varieties of necessity. However, this approach places the counterfactual conditionals in an unfamiliar foundational role.