In this paper, I elucidate the main points involved in the question of the non-triviality of the conventionality of simultaneity within the kinematics of special relativity. I argue that there is an important distinction to be made between the inherited component and the sui generis component of the conventionality of simultaneity. The factual core of the kinematics of special relativity is explored, and it is shown that the Round-Trip Clock Retardation effect obtains if, and only if Winnie's Passage Time Principle holds. Some consequences of this fundamental fact are then explored. In particular, Grünbaum's view that the epistemological conventionality of simultaneity is logically prior to the physical inter-frame relativity of simultaneity is found to be based largely on what I call the inherited component of the former. Finally, a question is raised as to the very self-consistency of the claim, made by Ellis and Bowman, that standard signal synchrony and slow-transport synchrony are logically independent. In some concluding remarks, the author's general agreement with Grünbaum's conception of bridled conventionalism is indicated.

In considering the possibility that the fundamental particles of matter might violate Leibniz's Principle, one is confronted with logical proofs that the Principle is a Theorem of Logic. This paper shows that the proof of that theorem is not universal enough to encompass entities that might not be unique, and also strongly suggests that photons, for example, do violate Leibniz's Principle. It also shows that the existence of non-individuals would imply the breakdown of Quine's criterion of ontological commitment.

In this paper Rudolf Carnap's definition of ‘analytic truth’ based upon a meaning postulate At, for theoretical predicates of a given scientific theory is subjected to critique. It is argued that this definition is both too exclusive and too inclusive. Assuming that the preceding is correct, At is subjected to further scrutiny to determine how to interpret it and whether, and under what conditions, it need even be true. It is argued that a given At need not be true as a sentence in a scientific theory and that it must be regarded as a confusedly presented rule for the same. It is then argued that even as a semantical rule for the theory, At cannot provide a guarantee of truth for some meaning postulate similar to At in the theory itself. It is thus argued that Carnap's definition of ‘analytic truth’ for theoretical predicates is unsatisfactory.

In this paper I shall be concerned primarily with contingent subjunctive conditionals, not to analyze them, but to argue that those who attempt such an analysis employing the concept of law—an approach which I confess seems promising—are at best providing logically sufficient conditions for the truth of contingent subjunctive conditionals and are not providing a correct analysis. My argument will have two parts. I shall first argue that the more plausible attempts to analyze our concept of law without subjunctive conditionals seem to fall prey to counter-examples. Secondly, I shall argue that even if we had an independent understanding of law, it is at least questionable that such an analysis could be employed in explicating conditions which are both logically necessary and sufficient for the truth of a subjunctive conditional.