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Poetry and philosophy have had a close but uneasy relationship in the western tradition. Both share an eschewal of the discovery of novel facts, but are somewhat opposed in that discovery is a central aim of poetry, but not at all the aim of philosophy. Through a close reading of W.H. Auden’s ‘In Memory of W.B. Yeats’ and a versification of part of G.E. Moore’s ‘A Defence of Common Sense’, I argue that what poetry shows corresponds, in a broadly symbolist sense, to Wittgenstein’s understanding of the miraculous nature of the world. In this regard, poetry can offer philosophy clarity, in the form of its tonal architecture, value, and ethics, and may also constitute a perspicuous representation. Poetry remains in a perpetual mode of potential, as well as being possessed of a vatic autonomy.

This article aims to add a further perspective to the discussion of the relationship between film and ethics. This perspective is important in today’s context, as the omnipresence of digital and mobile audiovisual images in everyday life increasingly determines our thinking and behaviour. However, there is a lack of appropriate critical reflection and ethical understanding of these images and their ontology. This article proposes a machine ethics of film from a film-philosophical perspective. Such an ethics draws on critical posthumanism, namely on Karen Barad’s “ethics of mattering”, which explicitly relates to Emmanuel Levinas’ philosophy of the Other and their death. Thereby, special attention is given to the ontological nexus of film and death, as well as to the idea of film’s spectrality (drawing on, e.g., Derrida, Barthes, and Leutrat), a context that is discussed along with Barad’s diffractive view on quantum entanglement. Following from the author’s earlier approaches to Barad’s agential realism in the context of film-philosophy and certain Heidegger-based arguments set out in earlier writings about film and death, this article introduces the figure of what is called the “machinic spectre of film”. From here, the outline of a possible spectral ethics of film is considered by giving reasons for the exploration of further questions.

This article examines some work by the Oaxaca-based Mexican experimental filmmaker and video artist Bruno Varela in order to explore the sense of Gilles Deleuze’s view that modern political cinema is characterized by a “missing” people, to which the adequate response is the people-sustaining or people-generating trance. I argue that the element missing from Deleuze’s discussion is how the typical way for a people to go “missing” under capitalism involves the obfuscation of their labor, an idea that sustains the materially grounded trance in Varela’s Papeles Secundarios (2004) and Cuerpos Complementarios (2022), drawn from the filmmaker’s experience as casting director of Iranian artist Shirin Neshat’s production of her video installation Tooba (2002) in Oaxaca. The article discusses the “baroque critique” involved in Varela’s elliptically representing the workday of the non-professional Oaxacan actors employed in Neshat’s production, understood here as a critique articulated using the detritus of that production. The result is a paradigm of trans-temporal playfulness on film that also challenges the claims to trans-temporal experience sought in Neshat’s work. Thus, the article also locates these arguments within debates about whether films can “do philosophy”, including a hypothesis about the obfuscations of labor lying behind why making-of documentaries—and their capacities to critique the philosophical pretensions of their original subjects—have not figured more centrally in those debates.

(1) Background: The rise of fascism in American and, indeed, throughout the world, prompts a question: why does fascism remain persistent in human existence? The question is one that Karl Jaspers might have asked regarding the origin and goal of history. The political description of fascism is not adequate to describe the lived experience of those drawn to it, and to assume such people to be irrational does not suffice. Rather, culture provides semiotic structure, which is phenomenologically embodied by people in a Mitwelt. (2) Results: Perhaps what is needed is not a political description of fascism but a communicological analysis that proceeds as a semiotic phenomenology of fascism as it is culturally embodied. Jaspers’ concept of evil frames fascism as colonialism turned against itself, disguised banally in such phenomena as Schadenfreude, as described by Lanigan. (3) I approach this question using a semiotic phenomenological method. (4) Conclusions: The fading colonial dominance in the form of cultural hegemony creates Laingian ontological insecurity and a desire for one’s inner fascist to identify itself in others. Addressing fascism requires new politics of experience.

This article explores the concept of landscape through the lens of performativity, challenging the traditional visual-centric understanding rooted in Western art and culture but without denying the visual and representational character of landscape. It examines the evolution of landscape representation, from its origins in linear perspective and Cartesian dualism to contemporary approaches that integrate performative practices. The analysis highlights the dialectical tension between visual representation and immersive, multisensory experiences, arguing for a more integrated view that acknowledges the performative aspects of the visual. By re-evaluating the role of distance, vision, and representation, the article advocates for a nuanced understanding of landscape that balances the visual with embodied practices, ultimately proposing that landscape should be seen as a dynamic interplay between seeing and performing.

In the literature on Kleene algebra, a number of variants have been proposed which impose additional structure specified by a theory, such as Kleene algebra with tests (KAT) and the recent Kleene algebra with observations (KAO), or make specific assumptions about certain constants, as for instance in NetKAT. Many of these variants fit within the unifying perspective offered by Kleene algebra with hypotheses, which comes with a canonical language model constructed from a given set of hypotheses. For the case of KAT, this model corresponds to the familiar interpretation of expressions as languages of guarded strings. A relevant question therefore is whether Kleene algebra together with a given set of hypotheses is complete with respect to its canonical language model. In this paper, we revisit, combine and extend existing results on this question to obtain tools for proving completeness in a modular way. We showcase these tools by giving new and modular proofs of completeness for KAT, KAO and NetKAT, and we prove completeness for new variants of KAT: KAT extended with a constant for the full relation, KAT extended with a converse operation, and a version of KAT where the collection of tests only forms a distributive lattice.

We investigate the impact of non-regular path expressions on the decidability of satisfiability checking and querying in description logics extending ALC. Our primary objects of interest are ALCreg and ALCvpl, the extensions of with path expressions employing, respectively, regular and visibly-pushdown languages. The first one, ALCreg, is a notational variant of the well-known Propositional Dynamic Logic of Fischer and Ladner. The second one, ALCvpl, was introduced and investigated by Loding and Serre in 2007. The logic ALCvpl generalises many known decidable non-regular extensions of ALCreg. We provide a series of undecidability results. First, we show that decidability of the concept satisfiability problem for ALCvpl is lost upon adding the seemingly innocent Self operator. Second, we establish undecidability for the concept satisfiability problem for ALCvpl extended with nominals. Interestingly, our undecidability proof relies only on one single non-regular (visibly-pushdown) language, namely on r#s# := { r^n s^n | n in N } for fixed role names r and s. Finally, in contrast to the classical database setting, we establish undecidability of query entailment for queries involving non-regular atoms from r#s#, already in the case of ALC-TBoxes.

The pebbling comonad, introduced by Abramsky, Dawar and Wang, provides a categorical interpretation for the k-pebble games from finite model theory. The coKleisli category of the pebbling comonad specifies equivalences under different fragments and extensions of infinitary k-variable logic. Moreover, the coalgebras over this pebbling comonad characterise treewidth and correspond to tree decompositions. In this paper we introduce the pebble-relation comonad, which characterises pathwidth and whose coalgebras correspond to path decompositions. We further show that the existence of a coKleisli morphism in this comonad is equivalent to truth preservation in the restricted conjunction fragment of k-variable infinitary logic. We do this using Dalmau's pebble-relation game and an equivalent all-in-one pebble game. We then provide a similar treatment to the corresponding coKleisli isomorphisms via a bijective version of the all-in-one pebble game. Finally, we show as a consequence a new Lov\'asz-type theorem relating pathwidth to the restricted conjunction fragment of k-variable infinitary logic with counting quantifiers.

The ZX-calculus is a powerful framework for reasoning in quantum computing. It provides in particular a compact representation of matrices of interests. A peculiar property of the ZX-calculus is the absence of a formal sum allowing the linear combinations of arbitrary ZX-diagrams. The universality of the formalism guarantees however that for any two ZX-diagrams, the sum of their interpretations can be represented by a ZX-diagram. We introduce a general, inductive definition of the addition of ZX-diagrams, relying on the construction of controlled diagrams. Based on this addition technique, we provide an inductive differentiation of ZX-diagrams. Indeed, given a ZX-diagram with variables in the description of its angles, one can differentiate the diagram according to one of these variables. Differentiation is ubiquitous in quantum mechanics and quantum computing (e.g. for solving optimization problems). Technically, differentiation of ZX-diagrams is strongly related to summation as witnessed by the product rules. We also introduce an alternative, non inductive, differentiation technique rather based on the isolation of the variables. Finally, we apply our results to deduce a diagram for an Ising Hamiltonian.

The logic of information flows (LIF) has recently been proposed as a general framework in the field of knowledge representation. In this framework, tasks of procedural nature can still be modeled in a declarative, logic-based fashion. In this paper, we focus on the task of query processing under limited access patterns, a well-studied problem in the database literature. We show that LIF is well-suited for modeling this task. Toward this goal, we introduce a variant of LIF called "forward" LIF (FLIF), in a first-order setting. FLIF takes a novel graph-navigational approach; it is an XPath-like language that nevertheless turns out to be equivalent to the "executable" fragment of first-order logic defined by Nash and Lud\"ascher. One can also classify the variables in FLIF expressions as inputs and outputs. Expressions where inputs and outputs are disjoint, referred to as io-disjoint FLIF expressions, allow a particularly transparent translation into algebraic query plans that respect the access limitations. Finally, we show that general FLIF expressions can always be put into io-disjoint form.

We study the extent to which it is possible to approximate the optimal value of a Unique Games instance in Fixed-Point Logic with Counting (FPC). Formally, we prove lower bounds against the accuracy of FPC-interpretations that map Unique Games instances (encoded as relational structures) to rational numbers giving the approximate fraction of constraints that can be satisfied. We prove two new FPC-inexpressibility results for Unique Games: the existence of a $(1/2, 1/3 + \delta)$-inapproximability gap, and inapproximability to within any constant factor. Previous recent work has established similar FPC-inapproximability results for a small handful of other problems. Our construction builds upon some of these ideas, but contains a novel technique. While most FPC-inexpressibility results are based on variants of the CFI-construction, ours is significantly different. We start with a graph of very large girth and label the edges with random affine vector spaces over $\mathbb{F}_2$ that determine the constraints in the two structures. Duplicator's strategy involves maintaining a partial isomorphism over a minimal tree that spans the pebbled vertices of the graph.

The author has recently introduced an abstract algebraic framework of analogical proportions within the general setting of universal algebra. This paper studies analogical proportions in the boolean domain consisting of two elements 0 and 1 within his framework. It turns out that our notion of boolean proportions coincides with two prominent models from the literature in different settings. This means that we can capture two separate modellings of boolean proportions within a single framework which is mathematically appealing and provides further evidence for the robustness and applicability of the general framework.

Logical relations built on top of an operational semantics are one of the most successful proof methods in programming language semantics. In recent years, more and more expressive notions of operationally-based logical relations have been designed and applied to specific families of languages. However, a unifying abstract framework for operationally-based logical relations is still missing. We show how fibrations can provide a uniform treatment of operational logical relations, using as reference example a lambda-calculus with generic effects endowed with a novel, abstract operational semantics defined on a large class of categories. Moreover, this abstract perspective allows us to give a solid mathematical ground also to differential logical relations -- a recently introduced notion of higher-order distance between programs -- both pure and effectful, bringing them back to a common picture with traditional ones.

When translating a term calculus into a graphical formalism many inessential details are abstracted away. In the case of $\lambda$-calculus translated to proof-nets, these inessential details are captured by a notion of equivalence on $\lambda$-terms known as $\simeq_\sigma$-equivalence, in both the intuitionistic (due to Regnier) and classical (due to Laurent) cases. The purpose of this paper is to uncover a strong bisimulation behind $\simeq_\sigma$-equivalence, as formulated by Laurent for Parigot's $\lambda\mu$-calculus. This is achieved by introducing a relation $\simeq$, defined over a revised presentation of $\lambda\mu$-calculus we dub $\Lambda M$. More precisely, we first identify the reasons behind Laurent's $\simeq_\sigma$-equivalence on $\lambda\mu$-terms failing to be a strong bisimulation. Inspired by Laurent's \emph{Polarized Proof-Nets}, this leads us to distinguish multiplicative and exponential reduction steps on terms. Second, we enrich the syntax of $\lambda\mu$ to allow us to track the exponential operations. These technical ingredients pave the way towards a strong bisimulation for the classical case. We introduce a calculus $\Lambda M$ and a relation $\simeq$ that we show to be a strong bisimulation with respect to reduction in $\Lambda M$, ie. two $\simeq$-equivalent terms have the exact same reduction semantics, a result which fails for Regnier's $\simeq_\sigma$-equivalence in $\lambda$-calculus as well as for Laurent's $\simeq_\sigma$-equivalence in $\lambda\mu$. Although $\simeq$ is formulated over an enriched syntax and hence is not strictly included in Laurent's $\simeq_\sigma$, we show how it can be seen as a restriction of it.

Quantum based systems are a relatively new research area for that different modelling languages including process calculi are currently under development. Encodings are often used to compare process calculi. Quality criteria are used then to rule out trivial or meaningless encodings. In this new context of quantum based systems, it is necessary to analyse the applicability of these quality criteria and to potentially extend or adapt them. As a first step, we test the suitability of classical criteria for encodings between quantum based languages and discuss new criteria. Concretely, we present an encoding, from a language inspired by CQP into a language inspired by qCCS. We show that this encoding satisfies compositionality, name invariance (for channel and qubit names), operational correspondence, divergence reflection, success sensitiveness, and that it preserves the size of quantum registers. Then we show that there is no encoding from qCCS into CQP that is compositional, operationally corresponding, and success sensitive.

Artykuł przedstawia model nadawczego aktu referencji komunikatywnej. Jest on ufundowany na dwóch innych aktach: akcie semantycznej referencji oraz akcie wczytania świata w adresata (akcie przypisania adresatowi roli odbiorcy). Oba akty są wzajemnie sprzężone poprzez akt metareferencji, dzięki któremu zanika Quine’owski efekt referencyjnego niezdeterminowania. Akt metareferencji jest wywoływany przez akt przypisania sobie roli nadawcy. Z kolei ten akt jest wywoływany przez akt wczytania świata w odbiorcę. Funkcją aktu metareferencji jest „wykonanie” fuzji aktu referencji semantycznej z aktem wczytania świata w adresata. Nad tym ostatnim aktem jest ufundowany lokowania odbiorcy w świecie, a nad nim akt konstytuowania ścieżki komunikacyjnej łączącej nadawcę z odbiorcą. W zależności od rodzaju aktu lokowania odbiorcy w świecie, konstytuowane ścieżki komunikacyjne mogą należeć do trzech kategorii: zakończonych, jedno-promiennych; zakończonych, wielo-promiennych oraz otwartych wielo-promiennych. Typ ścieżki determinuje typ więzi fizycznej łączącej nadawcę ze światem wczytanym w adresata. Nad aktem referencji semantycznej, skierowanym do adresata, jest ufundowany akt typizacji odbiorcy. Ten ostatni akt wraz z aktem wczytania świata w odbiorcę stanowią ufundowanie dla aktu konstytuowania bramek komunikatywnych w świecie wczytanym w odbiorcę. Bramki te determinują oczekiwany przez nadawcę sposób kwitowania odbioru transmisji komunikatywnej, przesyłanych do odbiorcy wiadomości na dany temat i w określony, oczekiwany sposób. Dzięki wszystkim wymienionym aktom składowym, nadawca ustanawia metrykę typizacyjną odbiorcy, czyli sposób, w jaki odbiorca jawi się nadawcy w procesie transmisji aktu referencji komunikatywnej.

Tennenbaum's theorem states that the only countable model of Peano arithmetic (PA) with computable arithmetical operations is the standard model of natural numbers. In this paper, we use constructive type theory as a framework to revisit, analyze and generalize this result. The chosen framework allows for a synthetic approach to computability theory, exploiting that, externally, all functions definable in constructive type theory can be shown computable. We then build on this viewpoint, and furthermore internalize it by assuming a version of Church's thesis, which expresses that any function on natural numbers is representable by a formula in PA. This assumption provides for a conveniently abstract setup to carry out rigorous computability arguments, even in the theorem's mechanization. Concretely, we constructivize several classical proofs and present one inherently constructive rendering of Tennenbaum's theorem, all following arguments from the literature. Concerning the classical proofs in particular, the constructive setting allows us to highlight differences in their assumptions and conclusions which are not visible classically. All versions are accompanied by a unified mechanization in the Coq proof assistant.

Angluin's L$^*$ algorithm learns the minimal deterministic finite automaton (DFA) of a regular language using membership and equivalence queries. Its probabilistic approximatively correct (PAC) version substitutes an equivalence query by numerous random membership queries to get a high level confidence to the answer. Thus it can be applied to any kind of device and may be viewed as an algorithm for synthesizing an automaton abstracting the behavior of the device based on observations. Here we are interested on how Angluin's PAC learning algorithm behaves for devices which are obtained from a DFA by introducing some noise. More precisely we study whether Angluin's algorithm reduces the noise and produces a DFA closer to the original one than the noisy device. We propose several ways to introduce the noise: (1) the noisy device inverts the classification of words w.r.t. the DFA with a small probability, (2) the noisy device modifies with a small probability the letters of the word before asking its classification w.r.t. the DFA, (3) the noisy device combines the classification of a word w.r.t. the DFA and its classification w.r.t. a counter automaton, and (4) the noisy DFA is obtained by a random process from two DFA such that the language of the first one is included in the second one. Then when a word is accepted (resp. rejected) by the first (resp. second) one, it is also accepted (resp. rejected) and in the remaining cases, it is accepted with probability 0.5. Our main experimental contributions consist in showing that: (1) Angluin's algorithm behaves well whenever the noisy device is produced by a random process, (2) but poorly with a structured noise, and, that (3) is able to eliminate pathological behaviours specified in a regular way. Theoretically, we show that randomness almost surely yields systems with non-recursively enumerable languages.

This paper presents a case study for the application of semiring semantics for fixed-point formulae to the analysis of strategies in B\"uchi games. Semiring semantics generalizes the classical Boolean semantics by permitting multiple truth values from certain semirings. Evaluating the fixed-point formula that defines the winning region in a given game in an appropriate semiring of polynomials provides not only the Boolean information on who wins, but also tells us how they win and which strategies they might use. This is well-understood for reachability games, where the winning region is definable as a least fixed point. The case of B\"uchi games is of special interest, not only due to their practical importance, but also because it is the simplest case where the fixed-point definition involves a genuine alternation of a greatest and a least fixed point. We show that, in a precise sense, semiring semantics provide information about all absorption-dominant strategies -- strategies that win with minimal effort, and we discuss how these relate to positional and the more general persistent strategies. This information enables applications such as game synthesis or determining minimal modifications to the game needed to change its outcome. Lastly, we discuss limitations of our approach and present questions that cannot be immediately answered by semiring semantics.

A classic result by Stockmeyer gives a non-elementary lower bound to the emptiness problem for star-free generalized regular expressions. This result is intimately connected to the satisfiability problem for interval temporal logic, notably for formulas that make use of the so-called chop operator. Such an operator can indeed be interpreted as the inverse of the concatenation operation on regular languages, and this correspondence enables reductions between non-emptiness of star-free generalized regular expressions and satisfiability of formulas of the interval temporal logic of chop under the homogeneity assumption. In this paper, we study the complexity of the satisfiability problem for suitable weakenings of the chop interval temporal logic, that can be equivalently viewed as fragments of Halpern and Shoham interval logic. We first consider the logic $\mathsf{BD}_{hom}$ featuring modalities $B$, for \emph{begins}, corresponding to the prefix relation on pairs of intervals, and $D$, for \emph{during}, corresponding to the infix relation. The homogeneous models of $\mathsf{BD}_{hom}$ naturally correspond to languages defined by restricted forms of regular expressions, that use union, complementation, and the inverses of the prefix and infix relations. Such a fragment has been recently shown to be PSPACE-complete . In this paper, we study the extension $\mathsf{BD}_{hom}$ with the temporal neighborhood modality $A$ (corresponding to the Allen relation \emph{Meets}), and prove that it increases both its expressiveness and complexity. In particular, we show that the resulting logic $\mathsf{BDA}_{hom}$ is EXPSPACE-complete.

By abstracting over well-known properties of De Bruijn's representation with nameless dummies, we design a new theory of syntax with variable binding and capture-avoiding substitution. We propose it as a simpler alternative to Fiore, Plotkin, and Turi's approach, with which we establish a strong formal link. We also show that our theory easily incorporates simple types and equations between terms.

The "Sum-Over-Paths" formalism is a way to symbolically manipulate linear maps that describe quantum systems, and is a tool that is used in formal verification of such systems. We give here a new set of rewrite rules for the formalism, and show that it is complete for "Toffoli-Hadamard", the simplest approximately universal fragment of quantum mechanics. We show that the rewriting is terminating, but not confluent (which is expected from the universality of the fragment). We do so using the connection between Sum-over-Paths and graphical language ZH-calculus, and also show how the axiomatisation translates into the latter. We provide generalisations of the presented rewrite rules, that can prove useful when trying to reduce terms in practice, and we show how to graphically make sense of these new rules. We show how to enrich the rewrite system to reach completeness for the dyadic fragments of quantum computation, used in particular in the Quantum Fourier Transform, and obtained by adding phase gates with dyadic multiples of $\pi$ to the Toffoli-Hadamard gate-set. Finally, we show how to perform sums and concatenation of arbitrary terms, something which is not native in a system designed for analysing gate-based quantum computation, but necessary when considering Hamiltonian-based quantum computation.

Abstract According to a particular interpretation of quantum mechanics, the causal role of human consciousness in the measuring process is called upon to solve a foundational problem called the “measurement problem.” Traditionally, this interpretation is tied up with the metaphysics of substance dualism. As such, this interpretation of quantum mechanics inherits the dualist’s mind-body problem. Our working hypothesis is that a process-based approach to the consciousness causes collapse interpretation (CCCI) -leaning on Whitehead’s solution to the mind-body problem- offers a better metaphysical understanding of consciousness and its role in interpreting quantum mechanics. This article is the kickoff for such a research program in the metaphysics of science.

Abstract I describe the key features of pure process realism-realism about the processes that are identified by experimental dynamics structured by scientific models-showing that the view meets criteria for scientific realism. I argue that process realism resolves many of the worries of the antirealist, including the problems of idealization, underdetermination, contextuality, multiplicity, and the pessimistic meta-induction. I show this resolution in the context of a contentious model from physics: the Bohr model of the atom. I then generalize from this discussion to a collection of upshots and constraints on process realism as a view, in order to further distinguish it from orthodox, substance-paradigmatic- or thing-realism. Therefore, pure process realism is shown to be a form of realism compatible with empiricism.

In this paper we shall define semantically some families of propositional modal logics related to the interpretability logic \(\mathbf{IL}\). We will introduce the logics \(\mathbf{BIL}\) and \(\mathbf{BIL}^{+}\) in the propositional language with a modal operator \(\square\) and a binary operator \(\Rightarrow\) such that \(\mathbf{BIL}\subseteq\mathbf{BIL}^{+}\subseteq\mathbf{IL}\). The logic \(\mathbf{BIL}\) is generated by the relational structures \(\left\), called basic frames, where \(\left\) is a Kripke frame and \(\left\) is a neighborhood frame. We will prove that the logic \(\mathbf{BIL}^{+}\) is generated by the basic frames where the binary relation \(R\) is definable by the neighborhood relation \(N\) and, therefore, the neighborhood semantics is suitable to study the logic \(\mathbf{BIL}^{+}\) and its extensions. We shall also study some axiomatic extensions of \(\mathsf{\mathbf{BIL}}\) and we will prove that these extensions are sound and complete with respect to a certain classes of basic frames. Finally, we prove that the logic BIL+ and some of its extensions are complete respect with the class of neighborhood frames.

In this paper, we rigorously prove the existence of type-level ordered pairs in Quine’s New Foundations with atoms, augmented by the axiom of infinity and the axiom of choice (NFU + Inf + AC). The proof uses the cardinal squaring principle; more precisely, its instance for the (infinite) universe (VCSP), which is a theorem of NFU + Inf + AC. Therefore, we have a justification for proposing a new axiomatic extension of NFU, in order to obtain type-level ordered pairs almost from the beginning. This axiomatic extension is NFU + Inf + AC + VCSP, which is equivalent to NFU + Inf + AC, but easier to reason about.

We present a syntactical cut-elimination proof for an extended sequent calculus covering the classical modal logics in the \(\mathsf{K}\), \(\mathsf{D}\), \(\mathsf{T}\), \(\mathsf{K4}\), \(\mathsf{D4}\) and \(\mathsf{S4}\) spectrum. We design the systems uniformly since they all share the same set of rules. Different logics are obtained by “tuning” a single parameter, namely a constraint on the applicability of the cut rule and on the (left and right, respectively) rules for \(\Box\) and \(\Diamond\). Starting points for this research are 2-sequents and indexed-based calculi (sequents and tableaux). By extending and modifying existing proposals, we show how to achieve a syntactical proof of the cut-elimination theorem that is as close as possible to the one for first-order classical logic. In doing this, we implicitly show how small is the proof-theoretical distance between classical logic and the systems under consideration.

GE algebras (generalized exchange algebras), transitive GE algebras (tGE algebras, for short) and aGE algebras (that is, GE algebras verifying the antisymmetry) are a generalization of Hilbert algebras. Here some properties and characterizations of these algebras are investigated. Connections between GE algebras and other classes of algebras of logic are studied. The implicative and positive implicative properties are discussed. It is shown that the class of positive implicative GE algebras (resp. the class of implicative aGE algebras) coincides with the class of generalized Tarski algebras (resp. the class of Tarski algebras). It is proved that for any aGE algebra the property of implicativity is equivalent to the commutative property. Moreover, several examples to illustrate the results are given. Finally, the interrelationships between some classes of implicative and positive implicative algebras are presented.

Western culture has assigned an essential role to productive activity in defining our lives. In Locke’s and Hegel’s thought, we see the model that became dominant in modern political philosophy: that of conceiving the subject as a result of, and only possible within, the triad of work–property–subject. Nowadays, this has reached the level of shaping the meaning of living, and our entire existences seem to be subjected to a concept of lives-as-work. Combining anthropology and philosophy, this article seeks to rethink subjectivation beyond the process of work and appropriation, delving into worldviews different from those of the West. Specifically, we will focus on the Yanomami form of life, a non-stratified indigenous people living in the Brazilian Amazon. We will analyze how the Yanomami prevent the process of subjectification by the objectification of one’s own work through a sort of anti-work and anti-property apparatus. This is achieved through specific techniques of underproduction, which constitute another approach to work, as well as through a completely different way of conceiving subjectivity. Furthermore, the Yanomami’s view of all entities as subjects endowed with intentionality appears as de-ontologizing the subject position and deactivating the dyads of subject/object and own/common. The result is a worldview where, with everyone being subjects—humans and non-humans, living and dead, entities and things of nature—no one can be dominus of anyone.

This article explores the issues of phenomenon and genesis in Early Buddhist thought through a comparative analysis with the Eleatic tradition, aiming to enrich the understanding and dialogue between these philosophical and religious traditions. By examining the comparability of Buddhist thought and Parmenidean philosophy, the study challenges the notion that these traditions are fundamentally alien to each other. The focus is on the concept of genesis, not as creation from nothingness—rejected by both the Buddha and Parmenides—but as the manifestation of the world to the human observer. The article argues that the world reveals itself in particular forms and appearances, which are intimately linked to the phenomenon and its perception by humans. This process is not solely a domain of rigid logical propositions but can be expressed through mythological and religious narratives. The study posits that the poetic expressiveness found in archaic philosophies of both India and Greece provides a valid medium for engaging in philosophical discourse. By adopting this comparative and dialogical perspective, the article aims to generate new philosophical insights and inspire future philosophical inquiry. The reflection on phenomenon and genesis, framed through this comparative lens, highlights the nuanced ways in which different traditions address the nature of reality and human perception, ultimately advocating for a broader, more inclusive understanding of philosophy that transcends conventional boundaries.

This paper aims to show how Kierkegaard’s attack upon Christendom still works today to contrast current forms of conformism disguised under the appearance of new secular religions. I will start with considering Kierkegaard’s concept of conformism as a form of despair. As such, conformism is incompatible with Christianity, as well as with the development of a true Self. Secondly, I will focus on the current religious scene in Western Europe. While Christianity has become a minority in society, new secular religions have arisen and, along with them, new compelling narratives. Mainstream environmentalism appears to be one of these. Finally, I will try to show how Kierkegaard’s arguments against Christendom can be also applied to environmental propaganda.

This paper provides a critical reflection and exploration of African development with reference to enhancing human flourishing in Amartya Sen’s capability theory. However, we identify some core limitations to Sen’s theory of development due to its reliance on neoliberal principles. These principles can be discouraging for African self-directed emancipatory development projects. We argue that the notion of communitarianism in Africa can provide alternative perspectives that can counter the influence of neoliberalism. We first delve into the philosophical understanding of development and the unique elements associated with the African context for human flourishing. From this understanding of development, we look into the work of Amartya Sen, whose capability approach is widely regarded as the optimal development project for human flourishing. However, the enhancement of capabilities has had some significant critique. We discuss three critiques of Sen’s development project, namely, Martha Nussbaum’s critique, which focuses on the vagueness of basic capabilities; Patrica Northover’s critique, which argues that Western ideals of development compromise Sen’s development project; and Richard Sandbrook’s critique, which refers to Sen’s approach as a “pragmatic neoliberalism”. Finally, building on these three critiques, we propose elements that enhance the unique characteristics of the African context for human flourishing.

The article discusses Nicholas Wolterstorff’s explanations for the flourishing of philosophical theology in analytic philosophy by taking Arthur Norman Prior’s (1914–1969) development of tense-logic into account. Prior’s work challenged the prevailing anti-metaphysical norms in analytic philosophy and introduced an alternative understanding of the relationship between logic and metaphysics. Prior’s application of tense-logic to an analysis of the concept of existence in quantified tense-logic and his exploration of future contingency in branching time semantics provide a strong reason for why analytic philosophy naturally incorporates philosophical theology. These considerations lead us to modify Wolterstorff’s emphasis on the importance of meta-epistemology for the resurgence of philosophical theology. A development in logic was necessary. Furthermore, Prior’s importance questions the assumption that philosophical theology was a consequence of theistic philosophers seeking ways to defend theistic beliefs in analytic philosophy. This is not true for Prior. His invention of tense-logic and discussion of omniscience was driven by an existential interest in finding answers to philosophical problems concerning divine foreknowledge and human freedom which ultimately led him to reject his Christian beliefs.

This essay reflects on the concept of the death of God as part and parcel of modern philosophical theology: a genre of thinking that came into existence with Hegel’s announcement of the “speculative Good Friday” as the most natural expression of die Religion der neuen Zeiten, “the religion of modern times”. In my interpretation, the death of God not only does not spell the end of the era of atheism but, on the contrary, inaugurates a new era of characteristically modern theism that steers away from theological absolutism. The new theos is no longer conceived as the eternal omnipotent Absolute but as the Derridean diminished Infinite: contracted and self-negated—even “unto death”. Such God, however, although coming to the foremost visibly in modernity, is not completely new to the monotheistic religions, which from the beginning are engaged in the heated debate concerning the status of the divine power: is it absolute and unlimited or rather self-restricted and conditioned? I will enter this debate by conducting a comparison between the two traditional models of divine self-restriction—Christian kenosis and Jewish-kabbalistic tsimtsum—and then present their modernised philosophical variants, most of all in the thought of Hegel.

This paper provides an epistemological and methodological analysis of the recent practice of using neural language models to simulate brain language processing. It is argued that, on the one hand, this practice can be understood as an instance of the traditional simulative method in artificial intelligence, following a mechanistic understanding of the mind; on the other hand, that it modifies the simulative method significantly. Firstly, neural language models are introduced; a study case showing how neural language models are being applied in cognitive neuroscience for simulative purposes is then presented; after recalling the main epistemological features of the simulative method in artificial intelligence, it is finally highlighted how the epistemic opacity of neural language models is tackled by using the brain itself to simulate the neural language model and to test hypotheses about it, in what is called here a co-simulation.

Some aspects of the concepts of counterfactuality and probability are explored as they apply to the specific example of the famous “EPR-Bell” experiments realized by physicists over the last half-century. In particular the question is raised: what hypotheses about actually conducted experiments do the results exclude? It is argued that the answer depends on both whether these hypotheses are deterministic or stochastic, and on the “cardinality” of the experiment relative to the theory.

Christian universalism, or the theory of universal salvation, is increasingly popular among religious thinkers. A small group of scholars has put forward the contentious claim that Kierkegaard was a universalist, despite that he refers in places to the idea of eternal damnation as essential to Christianity. This paper examines the evidence both for and against the view that Kierkegaard was a universalist and concludes that despite Kierkegaard’s occasional references to the importance of the idea of eternal damnation to Christianity, there is reason to believe that Kierkegaard may have been a universalist, both in terms of the substance of his thought, including two unequivocal statements in his journals that he believed everyone would eventually be saved and in terms of his rhetorical style which prioritizes the effect his writings would have on the reader over the literal truth of the views they present.

The relationship between science and philosophy is contentious. Quine saw philosophy as continuous with science (broadly understood), but many philosophers see a dichotomy between them. The present paper discusses cases where the relevance of certain scientific findings has been denied (related to Zeno’s Dichotomy paradox and to the appeal of skeptical arguments) or overlooked (one argument related to the frame problem of artificial intelligence and Nagel’s “bat” argument). The results caution against overly quick dismissal of the import of science on philosophical questions, whether the latter be of a more theoretical or practical nature.

Theoretically, a poem can begin in any way. What does it mean that in practice, poems often begin in a particular way—that is, by returning to a fragment of some prior thing? We see this in the encore of John Milton’s opening to Lycidas (‘Yet once more, O ye laurels, and once more’); differently, we see this in the widely used convention of the poetic epigraph (for instance, T. S. Eliot’s ‘The Love Song of J. Alfred Prufrock’ begins with six lines from Dante’s Inferno). While there is an established model for understanding the beginning as an act that invokes poetic precedent, this paper seeks to expose the beginning’s logic of return to a broader sense of language that is beyond the remit of poetic tradition as such. With a focus on the epigraph, this paper thinks about the everyday existence of poems and about how this existence relates to ordinary language, asking, how do these different modes of language function together? How does ordinary language collude in the creation of poetry? In its enactment of the passage of language from one mode of existence to another, the beginning of a poem might offer some answers to these questions.

For many 20th century philosophers, the “death of God” became an opportunity to rethink the limits of the human, eliminating its claims to a transcendent foundation in order to start again, more modestly, “from below”. The new humanity, freed from the burdens of the old metaphysics, becomes able to reappropriate responsibility, rediscovering in the other an irreducible presence. The human and philosophical story of Sarah Kofman offers the possibility of following an original development in this sense, starting from the unspeakable event of the Shoah towards a new possibility for human kind.

In this paper I attempt to trace the semiotic path of meaning experience from “nothing” into “something”. Traditional communication studies are problematic in 1. focusing on the message to the effect of ignoring the communicators; 2. choosing to overlook how yet-to-be signs acquire meanings in the communicative moments; and 3. tending to assume a “natural science” attitude toward the studied phenomenon so that embodied consciousness is either sidetracked or psychologized. Taking communicology as both the theory and methodology, I first describe the semiotic network in which blank paper, a nonconventional sign, acquires its signness in a specified communicative event. Then, I look inward to the relation of consciousness and embodiment. Finally, I argue that communication is such a life-world moment wherein non-expression is collectively constituted as a form of expression.

The outputs of a Turing machine are not revealed for inputs on which the machine fails to halt. Why is an observer not allowed to see the generated output symbols as the machine operates? Building on the pioneering work of Mark Burgin, we introduce an extension of the Turing machine model with a visible output tape. As a subtle refinement to Burgin’s theory, we stipulate that the outputted symbols cannot be overwritten: at step i, the content of the output tape is a prefix of the content at step j, where i

This article begins with critical discussion of why parochialism is so alluring, suggesting that we need to understand its tenacious seductions if we really aim to displace, uproot, or transcend it. Arguing that parochialism as a value is not primarily a question of ignorance, but an antipathetic orientation toward incompleteness, interdependency, and entanglement, it then turns briefly to explaining what is meant by creolizing theory. The article closes by offering creolizing’s central insights as a potential antidote to parochialism since they begin with the observation that for any lifeways to meaningfully continue, especially those to which we are most attached, they must be constantly resituated, refashioned, and made new. It ends with a brief meditation on ways to manage anxieties unleashed with radical uncertainty, affirming the depth of the challenges of turning from idolatry.

There is a curious moment in the balcony scene in Romeo and Juliet. Thinking she speaks in solitude, Juliet says, “Romeo, doff thy name, / And, for thy name, which is no part of thee, / Take all myself”. Emerging from the shadows, Romeo replies, “I take thee at thy word” (Act 2, Scene 1, 92). Suddenly, Juliet’s utterance has seemingly become binding: because they have been overheard by Romeo, her words have become her word. But is Juliet truly bound by her words given that she did not know they were being overheard, let alone intend for them to be binding? Using J. L. Austin’s notion of the performative, I consider the nature and status of Juliet’s utterance, its influence on the remainder of the scene, and what insight it might afford into the play as a whole.

Ulrika Carlsson has argued that it its justified to harbor non-moral resentment towards a person with whom one is unrequitedly in love. Anca Gheaus has rejected this with convincing arguments. This text explores the question of whether Gheaus’ verdict changes if the person being loved has previously flirted with the loving person. For this, it is first relevant what flirting actually is and how it relates to falling in love and love. On this basis, it is argued here that in the case of flirting, the non-moral resentment of the loved person defended by Carlsson is appropriate. By flirting, he or she has contributed to the unrequited love, even if he or she cannot be held responsible for it in a moral sense.

This essay begins with preliminary observations about the nature of agnosticism. Based on the term’s etymology, in this essay an agnostic about some proposition (e.g., God exists) is someone who does not know whether the proposition is true. Being an agnostic about the truth of a proposition is compatible with the proposition appearing to be true or the state of affairs obtains but incompatible with an agnostic knowing its truth or that the state of affairs obtains. (Reference to propositions and states of affairs is intended to be inclusive, rather than a controversial metaphysical distinction.) Based on apparent virtues and vices, reasons are offered about when agnosticism (or the profession of agnosticism) is virtuous or philosophically desirable and when either actual agnosticism or its profession seems to be a vice or undesirable. The essay concludes with challenging Anthony Kenny’s case for agnosticism about theism based on the virtue of humility. The central claims about apparent virtues and vices rest on the positive epistemic standing of appearances as defended by many so-called “common sense philosophers” Thomas Reid, Roderick Chisholm, and, more recently, Thomas Nagel’s thesis about the justified status of the appearance of values.

This essay assesses the relevance of Søren Kierkegaard’s non-pseudonymous, edifying writings for considering themes of desire, detachment, and humility within the religious context of Christian spiritual formation. Building on the argument of recent scholars who identify in Kierkegaard’s writings an account of a fundamental desire for God “implanted” in the human being, I explore the influence of this vision on Kierkegaard’s depiction of desire and detachment in his “Discourses on the Lilies and the Birds”. I then turn to how this relates to the perspective of humility that emerges from Kierkegaard’s reflections on the biblical story of “the widow’s mite”. In each case, these edifying writings aim to stir the reader into a process of interrogating faulty self-perceptions based on arbitrary measures of value. I read this mode of communication as able to initiate a “counter-experience”, provoking the reader to reorient her horizon of prior self-valuations so she might come to recognize the hidden significance of things and, ultimately, achieve a more accurate sense of oneself in relation to the authentic source of the self’s desire. Insofar as this reorientation of the self informs the practice of detachment or the development of humility, people might experience this same process in diverse ways. In this respect, the relevance of Kierkegaard’s edifying writings for reflecting on Christian spirituality is not that they provide a thoroughgoing account of detachment or humility that should replace the insights of various spiritual traditions. Rather, I argue that his discourses—when read alongside these traditions—offer a supplemental resource for reflecting on how our positionalities, dispositions, and proximate contexts will inform the divergent ways we might experience the practice of detachment or the manifestation of humility in each new life circumstance.

In continental and analytical philosophy, which developed in parallel in the 20th century, there was a turn to language, which in particular was marked by the creation of a philosophy of dialogue in continental philosophy and dialogical logic in analytical. Despite their significant differences, these two directions have much in common and can significantly complement each other. The philosophy of dialogue considers reality as the subject of dialogue between persons—I, Thou, He/She, We. World, activity and culture are dialogic and interpersonal in nature. Languages and texts are the basis for understanding reality and activity. Dialogical logic describes reality as an object of a dialogical game. This allows us to consider rationality, activity and communication from a unified perspective. The article compares these two directions of dialogical thought with each other and examines the aspects in which they can complement each other.

In this paper I hope to cast light on Wittgenstein enigmatic remark, “one should really only create philosophy poetically”. I discuss Wittgenstein’s ambition to overcome metaphysics by way of an appeal to ordinary language. For this purpose I contrast “realism” in philosophy (i.e., metaphysical realism, particularly its modern scientific version) with “realism” in poetry. My theme is the capacity of poetry to provide a model for Wittgenstein’s resistance to the inhumanity unleashed in metaphysics—exemplified by two distinct forms of skepticism—which obliterates the ordinary world under the guise of discovering its true nature. The poem I shall use to illustrate the difficulty in maintaining our grip on reality, hence our grip on our humanity, is Czeslaw Milosz’s poem “Realism”.