The existence of superluminal particles is consistent with relativistic dynamics

Within an axiomatic framework, we prove that the existence of faster than light (FTL) particles is consistent with (does not contradict) the dynamics of Einstein's special relativity. The proof goes by constructing a model of relativistic dynamics where FTL particles can move with arbitrary speeds. To have a complete picture, we not only construct an appropriate model but explicitly list all the basic assumptions (axioms) we use.     

Continuity and geometric logic

This paper is largely a review of known results about various aspects of geometric logic. Following Grothendieckʼs view of toposes as generalized spaces, one can take geometric morphisms as generalized continuous maps. The constructivist constraints of geometric logic guarantee the continuity of maps constructed, and can do so from two different points of view: for maps as point transformers and maps as bundles.     

THE INTERPLAY OF DEDUCTIVE AND INDUCTIVE REASONING IN PSYCHOANALYTIC THEORIZING

Deductive and inductive reasoning both played an essential part in Freud's construction of psychoanalysis. In this paper, the author explores the happy marriage of empiricism and rationalism in Freud's use of deductive reasoning in the construction of psychoanalytic theory. To do this, the author considers three major amendments Freud made to his theory: (i) infant and childhood sexuality, (ii) the structural theory, and (iii) the theory of signal anxiety. Ultimately, the author argues for, and presents Freud as a proponent of, the epistemological position that he calls critical realism.     

Clinical applications of Matte Blanco's thinking

Ignacio Matte Blanco (1908–1995) left very few specific indications about the applications of his theoretical notions to his interpretative style. The author shows how he uses Matte Blanco to formulate some of his own interpretations. The first part of the paper uses clinical vignettes to illustrate some of Matte‐Blanco's concepts. Their theoretical vocabulary is thus made explicit. Then two psychoanalytic sessions are discussed at greater length, together with one from a therapy, so that the use of Matte‐Blanco's notions can be seen clearly, allowing for a fresh perspective on areas of psychoanalytic theory, particularly dreams, psychopathology viewed according to the proportions of asymmetrical and symmetrical functioning in the patient's bi‐logical mental system, the multidimensionality of the unconscious, the structural unconscious, the emotion‐thought relationship, projective identification, resistance, and negative therapeutic reaction. The practical consequences of all this are elaborated, particularly the ensuing possibility of ‘thinking with the patient' in the session. This enables the patient to introject a form of mental functioning in which the asymmetrical mode is not invaded by the symmetric mode (a parallel can be seen here with the Bionian concept of dialogue between the psychotic and non‐psychotic parts of the mind).     

Truth Analysis of the Gettier Argument

Gettier (1963) presented the now famous Gettier problem as a challenge to epistemology. The methods Gettier used to construct his challenge, however, utilized certain principles of formal logic that are actually inappropriate for the natural language discourse of the Gettier cases. In that challenge to epistemology, Gettier also makes truth claims that would be considered controversial in analytic philosophy of language. The Gettier challenge has escaped scrutiny in these other relevant academic disciplines, however, because of its façade as an epistemological analysis. This article examines Gettier's methods with the analytical tools of logic and analytic philosophy of language.     

Philosophical foundations of partial belief models

This paper is an attempt to put forward a new kind of partial model for representing belief states. I first introduce some philosophical motivations for working with partial models. Then, I present the standard (total) model proposed by Hintikka, and the partial models studied by Humberstone and Holliday. I then show how to reduce Hintikka’s semantics in order to obtain a partial model which, however, differs from Humberstone’s and Holliday’s. The nature of such differences is assessed, and I provide motivations for using the newly proposed semantics rather than the existing ones. Finally, I review some promising philosophical applications of the ideas developed throughout the discussion.     

A multiple-valued logic approach to the design and verification of hardware circuits

We present a novel approach, which is based on multiple-valued logic (MVL), to the verification and analysis of digital hardware designs, which extends the common ternary or quaternary approaches for simulations. The simulations which are performed in the more informative MVL setting reveal details which are either invisible or harder to detect through binary or ternary simulations. In equivalence verification, detecting different behavior under MVL simulations may lead to the discovery of a genuine binary non-equivalence or to a qualitative gap between two designs. The value of a variable in a simulation may hold information about its degree of truth and its “place of birth” and “date of birth”. Applications include equivalence verification, initialization, assertions generation and verification, partial control on the flow of data by prioritizing and block-oriented simulations. Much of the paper is devoted to theoretical aspects behind the MVL approach, including the reason for choosing a specific algebra for computations and the introduction of the notions of De Morgan Canonical Form and of verification complexity of Boolean expressions. Two basic simulation-based algorithms are presented, one for satisfying and verifying combinational designs and the other for equivalence verification of sequential designs.     

Bunched sequential information

It is known that the logic BI of bunched implications is a logic of resources. Many studies have reported on the applications of BI to computer science. In this paper, an extension BIS of BI by adding a sequence modal operator is introduced and studied in order to formalize more fine-grained resource-sensitive reasoning. By the sequence modal operator of BIS, we can appropriately express “sequential information” in resource-sensitive reasoning. A Gentzen-type sequent calculus SBIS for BIS is introduced, and the cut-elimination and decidability theorems for SBIS are proved. An extension of the Grothendieck topological semantics for BI is introduced for BIS, and the completeness theorem with respect to this semantics is proved. The cut-elimination, decidability and completeness theorems for SBIS and BIS are proved using some theorems for embedding BIS into BI.     

Can Hardcore Actualism Validate S5?

Hardcore actualism (HA) grounds all modal truths in the concrete constituents of the actual world (see, e.g., Borghini and Williams (2008), Jacobs (2010), Vetter (2015)). I bolster HA, and elucidate the very nature of possibility (and necessity) according to HA, by considering if it can validate S5 modal logic. Interestingly, different considerations pull in different directions on this issue. To resolve the tension, we are forced to think hard about the nature of the hardcore actualist’s modal reality and how radically this departs from possible worlds orthodoxy. Once we achieve this departure, the prospects of a hardcore actualist validation of S5 look considerably brighter. This paper thus strengthens hardcore actualism by arguing that it can indeed validate S5–arguably the most popular logic of metaphysical modality–and, in the process, it elucidates the very nature of modality according to this revisionary, but very attractive, modal metaphysics.