Essentialism can be defined as a metaphysical theory according to which things have essential and accidental properties. In this paper, I will address Avicennian essentialism, that is, essentialism...

In _Essentialität und Notwendigkeit: Avicenna und die Aristotelische Tradition_ stellt Fedor Benevich Avicennas Theorie der Essenz und der wissenschaftlichen Bestimmung essentieller und notwendiger Attribute in einem historischen Kontext der aristotelischen Tradition. In _Essentialität und Notwendigkeit: Avicenna und die Aristotelische Tradition_ Fedor Benevich presents Avicenna’s theory of essence and the scientific determination of essential and necessary attributes in its historical context of the Aristotelian tradition.

RésuméQuels sont les objets de la perception? Deux réponses célèbres à cette question soutiennent que ce sont soit les images des objets extramentaux, c'est-à-dire la façon dont ils nous apparaissent, soit les objets eux-mêmes. Dans cet article, je présente une analyse de cette question par Abū l-Barakāt al-Baġdādī, un savant post-avicennien dont l'impact sur l'histoire de la philosophie islamique a été largement négligé. Abū l-Barakāt s'est opposé au dualisme épistémologique traditionnel aristotélicien-avicennien, qui établit une distinction entre la perception sensorielle des (...) particuliers matériels et la conception des universaux immatériels, notamment en ce qui concerne le percevant et/ou la structure de la perception. Selon la théorie d'Abū l-Barakāt, tous les actes épistémiques ont la structure unifiée d'une relation directe entre un même percevant et les objets eux-mêmes – matériels et immatériels. Sa thèse principale consiste à dire qu'avoir des organes corporels n'est pas nécessaire pour la perception sensorielle. Dans la dernière section de cet article, je montre que la critique d'Abū l-Barakāt de la tradition aristotélicienne-avicennienne fut considérée comme une innovation révolutionnaire en épistémologie. Cela peut avoir déterminé les théories épistémologiques de deux des philosophes arabes postavicenniens les plus importants : Faḫr al-Dīn al-Rāzī et Šihāb al-Dīn al-Suhrawardī. (shrink)

This is a translation of an article which appeared in 1928 in the journal Red Virgin Soil (Krasnaya nov) founded by Aleksandr Voronsky. Its author, the Russian Marxist Fedor Kapelusz, makes use of the now largely-ignored book of Algie Simons, Social Forces in American History (1911). In comparing America’s past to its present, Kapelusz offers a sharp political assessment and at the same time a contribution to the materialist conception of American history.

ABSTRACTScholarship on medieval philosophy has rightfully acknowledged the historical and systematical merit of Avicenna’s thought in all divisions of philosophy. Avicenna however did not...

How could perceptual experiences reveal matters of essentiality? Answering this question is crucial for vindicating a thesis about the epistemic import of experience, commonly known as Revelation. The thesis comes in a weak and a strong version. Only on the strong one could it make up an authoritative piece of common sense. But this version also seems to demand too much of our experiences, namely that they can reveal essentiality. However, the impression that our experiences are not suited for this (...) turns out to be due to a non-mandatory assumption about how the revelation of essentiality would work. (shrink)

It is well-known that natural axiomatic theories are well-ordered by consistency strength. However, it is possible to construct descending chains of artificial theories with respect to consistency strength. We provide an explanation of this well-orderedness phenomenon by studying a coarsening of the consistency strength order, namely, the$\Pi ^1_1$reflection strength order. We prove that there are no descending sequences of$\Pi ^1_1$sound extensions of$\mathsf {ACA}_0$in this ordering. Accordingly, we can attach a rank in this order, which we call reflection rank, to any$\Pi (...) ^1_1$sound extension of$\mathsf {ACA}_0$. We prove that for any$\Pi ^1_1$sound theoryTextending$\mathsf {ACA}_0^+$, the reflection rank ofTequals the$\Pi ^1_1$proof-theoretic ordinal ofT. We also prove that the$\Pi ^1_1$proof-theoretic ordinal of$\alpha $iterated$\Pi ^1_1$reflection is$\varepsilon _\alpha $. Finally, we use our results to provide straightforward well-foundedness proofs of ordinal notation systems based on reflection principles. (shrink)

Many social epistemologists suggest that testimonies may be considered a valid source of knowledge, no less than, for instance, direct observation. In this article, I will focus on the accounts of testimonial knowledge in classical kalām and Islamic law. I will present the arguments for why Islamic philosophers and jurists believe that testimonies convey knowledge. I will address the main disagreement in Islamic philosophy regarding the nature of testimonial knowledge, whether we can apply an internalist model of epistemic justification to (...) testimonial knowledge or not. I will suggest that the best way to understand the traditional view on testimonial knowledge in Islamic philosophy and law is as “weak testimonial reliabilism”: testimonial knowledge typically results from the occurrence of certain external conditions (of which we might be unaware), even though they hold only insofar as our experience of this world tells us so, and may not hold in another possible world. (shrink)

A central question in the history of metaphysics concerns the ontological status of such notions as 'redness,' 'humanity,' or 'animality,' which one calls 'universals.' Since one uses these notions to describe objects in the real world, it may seem intuitive that they exist in extramental reality: one says that universals are 'real'. Famously, though, several problems arise from this view. A central problem known both to medieval and contemporary scholars goes as follows: I look at a red rose and recognize (...) that there is 'redness' in it. Then, I look at a red apple and recognize that there is 'redness' in it, too. Does this mean that one and the same 'redness' appears in both the rose and the... (shrink)

According to the restructuring hypothesis, insight problem solving typically progresses through consecutive stages of search, impasse, insight, and search again for someone, who solves the task. The order of these stages was determined through self-reports of problem solvers and has never been verified behaviorally. We asked whether individual analysis of problem solving attempts of participants revealed the same order of problem solving stages as defined by the theory and whether their subjective feelings corresponded to the problem solving stages they were (...) in. Our participants tried to solve the Five-Square problem in an online task, while we recorded the time and trajectory of their stick movements. After the task they were asked about their feelings related to insight and some of them also had the possibility of reporting impasse while working on the task. We found that the majority of participants did not follow the classic four-stage model of insight, but had more complex sequences of problem solving stages, with search and impasse recurring several times. This means that the classic four-stage model is not sufficient to describe variability on the individual level. We revised the classic model and we provide a new model that can generate all sequences found. Solvers reported insight more often than non-solvers and non-solvers reported impasse more often than solvers, as expected; but participants did not report impasse more often during behaviorally defined impasse stages than during other stages. This shows that impasse reports might be unreliable indicators of impasse. Our study highlights the importance of individual analysis of problem solving behavior to verify insight theory. (shrink)

One of the most widespread claims combining epistemology and metaphysics in post-Avicennian Islamic philosophy was that every object of thought is real. In Muʿtazilite reading, it was endorsed due to a theory of knowledge which states that knowledge is a connection or relation between the knower and the object known. Avicennists accepted it due to the rule that in a proposition “s is p” if p is something positive s has to be positive and real too. Hence, insofar as one (...) can conceptually distinguish between two non-existent items, they have to be real. In this article, the author presents significant consequences of this theory: the acceptance and denial of non-existent yet real extramental objects; the concept of mental existence as an alternative solution; the conceivability of paraconsistent ideas and their reality or reducibility to some real objects. (shrink)

I propose that the fundamental challenge Berkeley left realists is to account for experiences’ ability to present items as mind-independent, consistent with the claim that experiences always present themselves among the items of awareness. By exploring two ways of responding to this challenge, and ruling out the second, I hope to show that realists aiming to secure a role for experiences in grounding our grasp of mind-independence need to adopt a specific view of perceptual experience. They must take experiences to (...) have translucent aspects, and accord such aspects an essential role in presenting us with a mind-independent world. (shrink)

We fix a gap in a proof in our paper Reducing ω-model reflection to iterated syntactic reflection.

The article attempts to explain the difficulty of systematization of philosophical categories. Philosophical categories are defined as common forms of cognitive and world view attitude of the man to the nature, society and his own existence. The article also analyses basic approaches to the process of creating the system of philosophical categories in the history of philosophical thought. The review of the major historical phases of philosophical interpretation of categories allows to state the existence of the problematic issue connected with (...) forming the system of categories. A lot of attempts have been undertaken on this subject. All of them were found controversial. It can be explained by the fact that all the attempts to systematize categories contradict the following principles - if categories are universal reflection forms of objective characteristics of existence, then their hierarchy must be the reflection of these characteristics’ hierarchy. But it is impossible to imagine that the "hierarchy" principle operates in the system of being, because the objective world is organized rather on the principle of "equality" than "subordination". The article addresses functional and developmental characteristics of philosophical categories. The article gives the author`s understanding of the concept of "philosophical categories". (shrink)

Avicenna's analysis of the definition of substance and accident repeatedly emphasizes two points: one and the same essence cannot be substance in one instance and accident in another; whetherxis extrinsic or intrinsic for an underlying subject,ydoes not tell us anything as to whetherxis substance or not. Both points are development in an argument against certain unnamed people who claimed the opposite. In this article I will show that Avicenna's opponents are to be identified with the mainstream Baghdad Peripatetic School which (...) based itself on the Late Antique rule that “parts of substances are substances”. As for Avicenna's own position, it was developed on the basis of the heterodox position of Yaḥyā b. ʿAdī, who anticipated Avicenna's first point. This is a further piece of evidence for something that has only recently begun to be appreciated: the influence of Ibn ʿAdī on Avicenna.RésuméL’analyse d’Avicenne portant sur les définitions de la substance et de l’accident met en exergue les deux propositions suivantes: 1) la même essence ne peut être à la fois une substance dans un cas et un accident dans un autre; 2) le fait quexsoit extrinsèque ou intrinsèque à unysous-jacent ne nous permet pas de conclure quexest une substance. Ces deux propositions sont articulées dans un débat avec d’autres personnes ayant un point de vue opposé dont on ne connaît pas l’identité. Dans cet article, nous verrons que ces adversaires font partie de l’école péripatétique de Bagdad, qui elle-même s’appuie sur une proposition datant de l’Antiquité tardive et selon laquelle les parties de substances sont elles-mêmes des substances. La position d’Avicenne fut développée à partir de celle de Yaḥyā b. ʿAdī. Cet article apporte ainsi un argument nouveau qui met en évidence l’influence, remarquée seulement depuis peu, d’Ibn ʿAdī sur Avicenne. (shrink)

The age of a structure M is the set of all isomorphism types of finite substructures of M. We study ages of generic expansions of ω-stable ω-categorical structures.

The concept of retroactive apparent occurrence, the main ingredient of Wheeler's delayed-choice thought experiments, is systematically incorporated into the quantum theory of measurement (in the framework of the recent review of Busch, Lahti, and Mittelstaedt). Besides, the (general) notion of individual-system measurement is introduced, and, due to it, premeasurement is defined by a truly minimal condition. Finally, retroactive apparent occurrence is made use of to derive apparent objectification in measurement. The derivation is discussed in the framework of the quantum mechanical (...) approach to the objectification problem. (shrink)

A short report on the trip to India.--Philosophical doctrine of Buddhism.--Logic in ancient India.--The doctrine of categorical imperative in the Brāhmaṇas.

We consider the well-known provability logic GLP. We prove that the GLP-provability problem for polymodal formulas without variables is PSPACE-complete. For a number n, let L0n\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${L^{n}_0}$$\end{document} denote the class of all polymodal variable-free formulas without modalities ⟨n⟩,⟨n+1⟩,...\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\langle n \rangle,\langle n+1\rangle,...}$$\end{document}. We show that, for every number n, the GLP-provability problem for formulas from L0n\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${L^{n}_0}$$\end{document} (...) is in PTIME. (shrink)

We give an example of a simple ω-categorical theory such that for any finite set of parameters the corresponding constant expansion does not satisfy the PAPA. We describe a wide class of homogeneous structures with generic automorphisms and show that some natural reducts of our example belong to this class.

In this paper, we study finitely axiomatizable conservative extensions of a theoryUin the case whereUis recursively enumerable and not finitely axiomatizable. Stanisław Krajewski posed the question whether there are minimal conservative extensions of this sort. We answer this question negatively.Consider a finite expansion of the signature ofUthat contains at least one predicate symbol of arity ≥ 2. We show that, for any finite extensionαofUin the expanded language that is conservative overU, there is a conservative extensionβofUin the expanded language, such that$\alpha (...) \vdash \beta$and$\beta \not \vdash \alpha$. The result is preserved when we consider eitherextensionsormodel-conservative extensionsofUinstead ofconservative extensions. Moreover, the result is preserved when we replace$\dashv$as ordering on the finitely axiomatized extensions in the expanded language by a relevant kind of interpretability, to witinterpretability that identically translates the symbols of the U-language.We show that the result fails when we consider an expansion with only unary predicate symbols for conservative extensions ofUordered by interpretability that preserves the symbols ofU. (shrink)

This paper makes explicit the basic problem perfect hallucinations pose for perceptual naive realists, more fundamental than the well‐trodden Screening‐off Problem. The deeper problem offers the basis for an overarching classification of the available naive‐ realist‐friendly approaches to perfect hallucinations. In the course of laying out the challenges to the different types of response, the paper makes a case for the superiority of a particular approach to perfect hallucinations, on which they would be understood as a special kind of perceptual (...) anomaly—arising from a secondary mode of perceptual processing. (shrink)

Is property-awareness constituted by representation or not? If it were, merely being aware of the qualities of physical objects would involve being in a representational state. This would have considerable implications for a prominent view of the nature of successful perceptual experiences. According to naïve realism, any such experience—or more specifically its character—is fundamentally a relation of awareness to concrete items in the environment. Naïve realists take their view to be a genuine alternative to representationalism, the view on which the (...) character of such experiences is constituted by representation. But naïve realists must admit qualities or property instances as items of awareness if they are to remain wedded to common sense, and the nature of property-awareness may smuggle constitutive representation into the naïve realist account of character. I argue that whether property-awareness involves representation, and consequently whether naïve realism is distinct from representationalism or not, depends on what qualities are fundamentally. On universalist and nominalist accounts, property-awareness turns out to involve representation. Not so under tropism. (shrink)

RésuméDans cet article, je soutiendrai que divers philosophes du kalām s'accordent à dire que la perception sensorielle dépasse les processus physiques dans les organes sensoriels. Il peut se passer quelque chose dans nos yeux lorsque nous voyons une pomme rouge, mais voir une pomme rouge ne s'y réduit pas. Nous verrons que certains philosophes du kalām soutiennent que la perception sensorielle est semblable à une prise de conscience ou à une conscience de l'objet de la perception, et qu'elle est, par (...) conséquent, distincte du processus physique dans les organes sensoriels. Un groupe ira jusqu’à accepter que la perception sensorielle ne dépend même d'aucun processus physique dans le corps. Un autre groupe acceptera que la perception sensorielle présuppose diverses conditions physiques, mais il considérera néanmoins la perception sensorielle comme quelque chose de distinct de l'occurrence de ces conditions. Je suggère que ces théories non réductionnistes de la perception sensorielle sont la raison pour laquelle les philosophes arabo-islamiques, à partir du XIe siècle, rejettent systématiquement la théorie aristotélico-avicennienne de la perception sensorielle. (shrink)

In this article we examine the main fragments of Thomas Aquinas regarding beauty. Our approach allows us to acquire the repertoire of definitions of beauty that are found in his commentaries and thought. Thus our scope is reconstruct at the theory of beauty that is implicit in Thomas Aquinas.

The theory of essential definitions is a fundamental anti‐sceptic element of the Aristotelian‐Avicennian epistemology. In this theory, when we distinguish the genus and the specific differentia of a given essence we thereby acquire a scientific understanding of it. The aim of this article is to analyse systematically the sceptical reasons, arguments and conclusions against real definitions of three major authorities of twelfth‐century Arabic philosophy: Faḫr al‐Dīn al‐Rāzī, Šihāb al‐Dīn al‐Suhrawardī and Abū l‐Barakāt al‐Baġdādī. I focus on showing how their refutation (...) of our capacity to provide essential definitions of things is rooted in their semantic theory: we only know things under certain descriptions which are identical to the meanings of the words that we use to refer to them, yet these descriptions do not capture the essences of things in themselves. The best result one can achieve with Aristotelian‐Avicennian scientific definitions is a “nominal definition”. With this, Rāzī, Suhrawardī and Abū l‐Barakāt will put some serious epistemic limitations on our capacity to attain scientific knowledge of things, at least as Aristotle and Avicenna would have it. (shrink)

The impacts that AI and robotics systems can and will have on our everyday lives are already making themselves manifest. However, there is a lack of research on the ethical impacts and means for amelioration regarding AI and robotics within tourism and hospitality. Given the importance of designing technologies that cross national boundaries, and given that the tourism and hospitality industry is fundamentally predicated on multicultural interactions, this is an area of research and application that requires particular attention. Specifically, tourism (...) and hospitality have a range of context-unique stakeholders that need to be accounted for in the salient design of AI systems is to be achieved. This paper adopts a stakeholder approach to develop the conceptual framework to centralize human values in designing and deploying AI and robotics systems in tourism and hospitality. The conceptual framework includes several layers – ‘Human-human-AI’ interaction level, direct and indirect stakeholders, and the macroenvironment. The ethical issues on each layer are outlined as well as some possible solutions to them. Additionally, the paper develops a research agenda on the topic. (shrink)

The article analyzes the process of group-dynamic change and the way of leading a training group in the transition from an on-site to a virtual form of work. This change is analyzed in the form of a case study, which describes the specifics of the pandemic crisis and the need to move to a virtual form of leadership. The change in the group dynamics is commented on, and the interventions of leaders are described, which make the crisis functioning more adaptable (...) and functional in relation to the task of the training group. (shrink)