Francesco Orilia

It is customary in current philosophy of time to distinguish between an A- (or tensed) and a B- (or tenseless) theory of time. It is also customary to distinguish between an old B-theory of time, and a new B-theory of time. We may say that the former holds both semantic atensionalism and ontological atensionalism, whereas the latter gives up semantic atensionalism and retains ontological atensionalism. It is typically assumed that the B-theorists have been induced by advances in the philosophy of language and related A-theorists’ criticisms to acknowledge that semantic atensionalism can hardly stand, but have also maintained that what is essential for the B-theory is ontological atensionalism, which can be independently defended. Here it is argued that the B-theorists have been too quick in abandoning semantic atensionalism: they can still cling to it

Konolige''s technical notion of belief based on deduction structures is briefly reviewed and its usefulness for the design of artificial agents with limited representational and deductive capacities is pointed out. The design of artificial agents with more sophisticated representational and deductive capacities is then taken into account. Extended representational capacities require in the first place a solution to the intensional context problems. As an alternative to Konolige''s modal first-order language, an approach based on type-free property theory is proposed. It considers often neglected issues, such as the need for a more general account of thede dicto-de re distinction, and quasi-indicators. Extended deductive capacities require a subdivision of Konolige''s notion of belief into two distinct technical notions,potential anddispositional belief. The former has to do with what an artificial agent could in principle come to actively believe, given enough time and its specific logical competence; the latter with what an agent can be assumed to believe with respect to a specific goal to be fulfilled.

I shall explain the notions of propositions and states of affairs as they are understood in the current ontological debate and I shall briefly relate them to similar notions in Aristotle and some Medieval authors. In contrast with the point of view of some philosophers who identify propositions and states of affairs, I shall argue that they need to be sharply distinguished. I shall then move on to a problem for propositions and, above all, states of affairs, known as Bradley’s regress, and hint at discussions of this or analogous puzzles in the philosophical tradition before Bradley. Finally, I shall present my own approach to this issue, Fact Infinitism, focusing on why it would have been hardly acceptable before ontology came to have the Cantorian conception of the infinite at its disposal

According to the received view, descriptivism is a dead end in an attempt to account for singular reference by proper names, indexicals and possibly even incomplete descriptions, for they require referentialism. In contrast to this, I argue for an application of the former to all kinds of singular terms, indexicals in particular, by relying on a view of incomplete descriptions as elliptical in a pragmatic sense. I thus provide a general analysis of singular reference. The proposed approach is in line with the classical theory of propositions, except for admitting “private” ones with subjective mental entities as constituents. On the other hand, there is no commitment to singular Russellian propositions with ordinary objects as constituents and in general to meanings that cannot be “in the mind”

Russell’s type theory has been the standard property theory for years, relying on rigid type distinctions at the grammatical level to circumvent the paradoxes of predication. In recent years it has been convincingly argued by Bealer, Cochiarella, Turner and others that many linguistic and ontological data are best accounted for by using a type-free property theory. In the spirit of exploring alternatives and “to have as many opportunities as possible for theory comparison”, this paper presents another type-free property theory, to be called P*, intended for applications in Montague-style natural language semantics and formal ontology. The theory is philosophically grounded on Gupta’s and Belnap’s revision theory of definitions and its basic idea is viewing predication (exemplification) as a ‘circular concept’ that can be captured by circular definitions. The paper has the following fourteen sections: (1) Introduction; (2) Formal type-free property theory; (3) Applying RTD [revision theory of definitions] to exemplification; (4) The system P*; (5) Some features of P*; (6) A comparison with Turner’s system; (7) Entailment and P*; (8) P* and natural language semantics; (9) Noun phrases; (10) The need for type-freedom in semantics; (11) Arithmetic in P*; (12) Arithmetic in PN*; (13) Complexity of P*; (14) Conclusion, and acknowledgments.

Dynamic events such as a rolling ball moving from one place to another involve change and time intervals and thus presumably successions of static events occurring one after the other, e.g., the ball’s being at a certain place and then at another place during the interval in question. When dynamic events are experienced they should count as present and thus as existent from a presentist point of view. But this seems to imply the existence of the static events involved in them. This in turn seems to imply that there exist past and perhaps even future static events. Therefore, there is a problem for presentism. A possible way out for the presentist is proposed, based on allowing for time-indexed past-oriented and future-oriented properties. One may raise objections regarding the ontological status of these properties and the commitment to past and future objects and times that they seem to bring with them, but these objections can be put to rest.