We exploit properties of certain directed graphs, obtained from the families of sets with special effective enumeration properties, to generalize several results in computable model theory to higher levels of the hyperarithmetical hierarchy. Families of sets with such enumeration features were previously built by Selivanov, Goncharov, and Wehner. For a computable successor ordinal α, we transform a countable directed graph into a structure such that has a isomorphic copy if and only if has a computable isomorphic copy.A computable structure (...) is categorical if for all computable isomorphic copies of , there is an isomorphism from onto , which is . We prove that for every computable successor ordinal α, there is a computable, categorical structure, which is not relatively categorical. This generalizes the result of Goncharov that there is a computable, computably categorical structure, which is not relatively computably categorical.An additional relation R on the domain of a computable structure is intrinsically on if in all computable isomorphic copies of , the image of R is . We prove that for every computable successor ordinal α, there is an intrinsically relation on a computable structure, which not relatively intrinsically . This generalizes the result of Manasse that there is an intrinsically computably enumerable relation on a computable structure, which is not relatively intrinsically computably enumerable.The dimension of a structure is the number of computable isomorphic copies, up to isomorphisms. We prove that for every computable successor ordinal α and every n≥1, there is a computable structure with dimension n. This generalizes the result of Goncharov that there is a structure of computable dimension n for every n≥1.Finally, we prove that for every computable successor ordinal α, there is a countable structure with isomorphic copies in just the Turing degrees of sets X such that relative to X is not . In particular, for every finite n, there is a structure with isomorphic copies in exactly the non- Turing degrees. This generalizes the result obtained by Wehner, and independently by Slaman, that there is a structure with isomorphic copies in exactly the nonzero Turing degrees. (shrink)

Chapter One: Constructions. Entities, constructions, and functions When one travels from Los Angeles to New York, going, say, by way of St. Louis, Chicago, ...

We will study the question about decidability for Boolean algebras with first elementary characteristic one. The main problem is sufficient conditions for decidability of Boolean algebras with recursive representation for extended signature by definable predicates. We will use the base definitions on recursive and constructive models from [2, 4–6, 10, 11] but on Boolean algebras from [1, 8].

A review of Jozef Kovalčik´s and Max Ryynänen´s Aesthetics of Popular Culture.

This research partially answers the question raised by Goncharov about the size of the class of positive elements of a Roger's semilattice. We introduce a notion of effective infinity of classes of computable enumerations. Then, using finite injury priority method, we prove five theorems which give sufficient conditions to be effectively infinite for classes of all enumerations without repetitions, positive undecidable enumerations, negative undecidable enumerations and all computable enumerations of a family of r.e. sets. These theorems permit to strengthen (...) the results of Pour-El, Pour-El and Howard, Ershov and Khutoretskii about existence of enumerations without repetitions and positive undecidable enumerations. (shrink)

It is widely held that oblique contexts and indexical terms present difficulties to Frege's theory of sense. The aim of the present paper is to show that a simple device involving no revision of Frege's semantic doctrine resolves all the alleged difficulties. A simple extension of Frege's notation is proposed which makes it possible to translate oblique contexts into the concept script.

The paper enters into a polemical dialogue with the american theorist Jodi Dean and her attempts to critically examine the blogosphere through the prism of psychoanalysis. To this end, the text analyses whether user-generated content on the internet can produce meaningful and epistemologically sustainable “social enclaves”, informal communities and institutions, or whether it operates more as a series of recursive and increasingly meaningless quasi-messages. While attempting to consider blogging as both a constructive practice and a pathology, the text develops the (...) hypothesis that in special cases one can conceptually speak of “epistemic inflation”, a phenomenon that can manifest itself at the personal as well as the social, economic and/or political level. Furthermore, the paper briefly introduces the ideas, history and one of the key concepts of the influential british theory-fiction collective, CCRU (Cybernetic Culture Research Unit). (shrink)

In my comment on Katerina Ierodiakonou’s paper, I outline my understanding of the programme of De anima and how it bears on Aristotle’s discussion of the transparent in De anima 2.7, in contrast with his discussion of the transparent in De sensu 3. I then explore Aristotle’s notion of transparency and sketch an alternative to Ierodiakonou’s interpretation of Aristotle’s views as to how colours are generated in physical objects. At the end, I raise two objections to Alexander’s interpretation of the (...) transparent as discussed by Ierodiakonou. (shrink)

Buzaglo (as well as Manders (J Philos LXXXVI(10):553–562, 1989)) shows the way in which it is rational even for a realist to consider ‘development of concepts’, and documents the theory by numerous examples from the area of mathematics. A natural question arises: in which way can the phenomenon of expanding mathematical concepts influence empirical concepts? But at the same time a more general question can be formulated: in which way do the mathematical concepts influence empirical concepts? What I want to (...) show in the present paper can be described as follows. The problem articulated by Buzaglo deserves some semantic refinements. Following explications are needed: What is meaning? (In particular: What are concepts?) What are questions? (Or, equivalently: Semantics of interrogative sentences.) -/- Further, a useful notion will be the notion of problem. Taking over the notion of conceptual system from Materna (Conceptual Systems. Logos, Berlin, 2004) and using Tichý’s Transparent intensional logic (TIL) I can try to solve the problem of the relation between mathematical and empirical concepts (not only for the case of expanding some mathematical concepts). (shrink)

Attempting to steer moral philosophy away from abstract theorizing, Moral Disquiet and Human Life argues that moral philosophy should be a practical, rational, and argumentative engagement with reality, and that moral reflection should have direct effects on our lives and the world in which we live. Illustrating her discussion with vivid examples from literature, music, drama, and current events, the noted French philosopher Monique Canto-Sperber resumes the most ancient pursuit of philosophy: the examination of human life itself. What did Socrates (...) mean when he said that the unexamined life is not worth living? How can reflecting on one's existence incorporate human singularity, the contingency of events, the certainty of death, the presence of the past, or the irreversibility of time? Carefully analyzing and proposing answers to such questions, Moral Disquiet and Human Life eloquently calls for a redefinition of the task of moral philosophy and of its limits. (shrink)

The paper deals with the etymology of the personal names Qunï Säŋün and Toŋra Simä appearing in the ninth line of the Old Turkic Tonyukuk inscription. These names are borne by the envoys sent by the kagan of the Tokuz Oghuz to the Chinese and Khitan, respectively, to conclude a military alliance against the Turks. Both names have the same structure, a combination of an ethnonym vs. toŋra), referring to a tribal unit within the Tiele 鐵勒 confederation, and a title (...) of Chinese origin. Based on a thorough analysis of historical and philological data, the authors try to establish possible ethnolinguistic grounds for the Tokuz Oghuz mission, which have so far eluded researchers of the inscription and can be fully restored only in the light of the latest discoveries in the history and philology of Inner Asia of the Old Turkic period, e.g., the decipherment of the famous Khüis Tolgoi inscription from Mongolia. (shrink)

European Journal of Philosophy, EarlyView.

In lieu of an abstract, here is a brief excerpt of the content:RUSSELLS ARGUMENT AGAINST FREGE'S SENSE-REFERENCE DISTINCTION PAWEL TURNAu Philosophy I Jagiellonian University Cracow, Poland I n "On Denoting"l Russell argued that Frege's theory of sense and reference was an "inextricable tangle", but, ironically, many readers found the argument even more knotry. In an effort to make sense of it, commentators were often driven to attribute to Russell quite obvious and simple fallacies. A different approach was taken by Peter (...) Geach, who suggested that Russell's argument could be given a consistent reading if it were construed as arguing, not against Frege's theory, but against Russell's own earlier theory, which he put forward in The Principles of Mathematics. It is not an implausible hypothesis, considering how prone Russell was to misrepresent' other philosophers' views and read his own powerful ideas into their writings. In order to justifY Geach's hypothesis properly, one would have to show the crucial difference between Russell's and Frege's theories that made only one of them susceptible to the attack in "On Denoting ". Russell explicitly considered the two theories to be "very nearly the same"; this self-interpretation would have to be questioned. Geach's hypothesis would be further strengthened by providing an actual exegesis of the "On Denoting" argument as directed against The Principles ofMathematics theory. In this paper 1 will try to accomplish both of these tasks. Russell is often accused of confusing use and mention. The accusation is not fair, however. It is true that he does not insist on this distinction; he does not employ it extensively. But he is certainly Russell's Argument against Frege's Distinction 53 aware of it; he simply does not think that it is an important logical distinction. Today this view may seem almost incomprehensible, but that only shows the strength of Frege's influence on our ideas. There are two striking symptoms of Russell's lack of concern for the use-mention distinction: firstly, he does not observe the convention which says that putting an expression in quotation marks produces a name of that expression; secondly, he does not feel any need to employ the pair of terms "sentence" and "proposition", but contents himself with the latter only. The claim about Russell's use of inverted commas needs to be proved; I will come to that later. Russell's assertions are often ambiguous between use and mention of expressions. For example, he asserts that "propositions do not contain words" (PaM, p. 47). However, a few pages later, he speaks of propositions that contain the phrase "any number" (p. 53). If this is not to be self-contradictory, then either the term "proposition" must sometimes signifY a linguistic expression, or the term "phrase" must sometimes be understood without implying that a phrase consists of words. This ambiguity is openly admitted in a later article, where he writes: [we shall be concerned with] the distinction between verbs and substantives, or, more correctly, between the objects denoted by verbs and the objects denoted by substantives. Since this more correct expression is long and cumbrous, I shall generally use the shorter expression to mean the same thing. Thus, when I speak of verbs, I mean the object denoted by verbs, and similarly for substantives.2. Russell's attitude towards the distinction between use and mention is not unjustified. It has its reason in his view oflanguage and the subject -matter of logic. In Russell's view, the subject-matter of logic has nothing to do with language. Words, both spoken and written, are entirely outside its realm. Logic, just as other sciences (except linguistics ), is concerned with the entities indicated by words, and not with words themselves. Even the relation of indicating, which holds between words and things in the world, is of no interest to it: "mean1 In Lf(, pp. 39-56. russ.lI: the Journal of the Bertrand Russell Archives McMaster Univecsity Library Press n.s. 11 (summer 1991): 51- 66 ISSN 0036-o16~ 2 B. Russell, "On the Relations of Universals and Particulars", Proceedings of the Aristotelian Society, n.s. 12 (r9II-12): 1-24; in Lf(, pp. 103-24 (at 107-8). 54 PAWEL TURNAU Russell's Argument... (shrink)

I. The framework. 1, Aristotle's project and methods. 2, The perceptual capacity of the soul. 3, The sensory apparatus. 4, The common sense and the related capacities -- II. The terminology. 1, Overlooked occurrences of the phrase 'common sense'. 2, De anima III.1 425a27. 3, De partibus animalium IV.10 686a31. 4, De memoria et reminiscentia 1 450a10. 5, De anima III.7 431b5. 6, Conclusions on the terminology -- III. Functions of the common sense. 1, Simultaneous perception and cross-modal binding. 2, (...) Perceptual discrimination. 3, Waking, sleep, and control of the senses. 4, Perceiving that what we see and hear, and monitoring of the senses. 5, Other roles of the common sense -- Conclusion. (shrink)

The article offers a rigorous truth condition for subjunctively conditional statements. The theory is framed in the system of transparent intensional logic and takes connections (especially the cause-Effect relation) as basic. Counterexamples are given to rival theories based on the notion of world similarity.

Jan Patočka’s philosophical development was varied. Over the course of fifty years of philosophizing, he gradually, and to varying degrees, developed close to a dozen systematic projects, whose ambition was, at least initially, to present what he called a “unified philosophy.” However, the dynamism with which he changed his philosophical plans and incessantly embarked on new projects invites the question of how to approach the various and often mutually “contradictory” transformations of his philosophical thinking, if neither the continuity and integrity (...) of Patočka’s thought nor the essential specificity of any of these positions is to be lost. Through the notion of the “personal a priori” found in one of Jan Patočka’s early texts, and in a critical, “overcoming-preserving” reference to two antagonistic conceptions of Patočka’s philosophical development, the article attempts to sketch a solution to this general interpretative problem. In the context of the search for Patočka’s “basic position of seeing” as the integrating framework of his diverse philosophical attempts, it simultaneously reconstructs the early question about the meaning of philosophy in general, which Patočka developed in a series of texts from the 1930s, some of which are still available only in the Czech language. (shrink)

We give an exponential lower bound on number of proof-lines in the proof system K of modal logic, i.e., we give an example of K-tautologies ψ₁, ψ₂,... s.t. every K-proof of ψi must have a number of proof-lines exponential in terms of the size of ψi. The result extends, for the same sequence of K-tautologies, to the systems K4, Gödel—Löb's logic, S and S4. We also determine some speed-up relations between different systems of modal logic on formulas of modal-depth one.

There are no moral entitlements with respect to pollution prior to legal conventions that establish them, or so I will argue. While some moral entitlements precede legal conventions, pollution is part of a category of harms against interests that stands apart in this regard. More specifically, pollution is a problematic type of harm that creates liability only under certain conditions. Human interactions lead to harm and to the invasion of others’ space regularly, and therefore we need an account of undue (...) harm as a basis of assigning legal protections and obligations to different agents, which creates standards for holding those agents responsible for harm. Absent such positive standards with respect to pollution at the domestic or international level, it does not make sense to hold agents responsible. This fact has two fundamental implications. First, contrary to what some defenders of environmental justice argue, we cannot hold people responsible for polluting without a system of legal rights in place that assigns entitlements, protections, and obligations, and second, contrary to what opponents of environmental regulation claim, the lack of moral entitlements to pollute creates room for quite extensive legal restrictions on people’s ability to pollute for the sake of the environment and human health. Indeed the scope of those restrictions is wide and open-ended. (shrink)

Problems are defined as abstract procedures. An explication of procedures as used in Transparent Intensional Logic and called constructions is presented and the subclass of constructions called concepts is defined. Concepts as closed constructions modulo α- and η-conversion can be associated with meaningful expressions of a natural or professional language in harmony with Church’s conception. Thus every meaningful expression expresses a concept. Since every problem can be unambiguously determined by a concept we can state that every problem is a concept (...) and every concept can be viewed as a problem.Kolmogorov’s idea of a connection between problems and Heyting’s calculus is examined and the non-classical features of the latter are shown to be compatible with realistic logic using partial functions. (shrink)

Pár slov úvodem k dopisu, který poslal Pavel Tichý z University of Otago Pavlu Maternovi (který v té době ´pracoval´ na brněnské univerzitě bez možnosti učení a publikování). K dataci dopisu: Shoduji se s odhadem Dr. Raclavského, že jde patrně o r. 1975. Ti, kdo neprožili normalizaci, si těžko představí situaci. To nebylo tak, že můj přítel Tichý momentálně působí na Novém Zélandě a píše mi z momentálního zahraničního pobytu. Tichý byl emigrant, což mj. znamenalo, že žádnou z jeho (...) odborných statí nebylo možno u nás citovat, dále že dík faktu, o kterém každý věděl, že dopisy emigrantů jsou u nás na příslušných institucích otvírány, znamenala korespondence s emigrantem kádrovou skvrnu. O tom jsem tehdy nepřemýšlel, už proto, že četba Tichého dopisů byla nesmírně zajímavá. Byl jsem na shromažďování korespondence lajdák. Moje krátkozrakost zavinila, že se z této korespondence zachoval nepatrný zlomek. Dopis, který následuje, je ovšem obzvlášť zajímavý, a to z následujícího důvodu: Tichý měl už od šedesátých let – ještě v Československu – v hlavě zárodky svého přístupu k logice a logické analýze přirozeného jazyka (svědčí o tom jeho stati v tehdejším Filosofickém časopise, zejména stať „Smysl a procedura“ z r. 1968). Dopis, který zde uveřejňujeme, má však hodnotu historického dokumentu. Jde o první ´neformální´ formulaci jeho pojetí tzv. konstrukcí a jeho postoje k logice, což se postupně promítlo do systému Transparentní intenzionální logiky (TIL), vyloženého souvisle v monografii The Foundations of Frege´s Logic, vydané asi 13 let po tomto dopisu. Ze vzhledu dopisu je patrné, že byl psán na psacím stroji, což v těch letech bylo standardní. Musíme omluvit překlepy (ostatně to byl osobní dopis), pokud jde o nespisovnosti, vím, že Tichý ovládal češtinu velmi dobře, ale dával přednost psát přirozeně, blízko k hovorové češtině. Jistě připustíte, že jeho jazyk je zde velmi živý a že úpravy směrem ke spisovnému jazyku by narušily kouzlo bezprostřednosti a jistého emocionálního zaujetí, které z dopisu vyzařuje. Tichý posílal mně a Pavlovi Cmorejovi i nadále jednak osobní dopisy, jednak rukopisy svých statí, takže jsme měli výhodu být účastni procesu budování TIL, kterou oba (a dnes už nejenom my) pokládáme za podstatný přínos ke světové logice. --Pavel Materna. (shrink)

Originally proposed by Prior, egocentric logic is a class of logical systems that capture properties of agents rather than of possible worlds. The article proposes a doxastic egocentric system with rigid names for reasoning about beliefs that an agent might have about herself.

Rédei and Gyenis recently displayed strong constraints of Bayesian learning. However, they also presented a positive result for Bayesianism. Despite the limited significance of this positive result, I find it useful to discuss its two possible strengthenings to present new results and open new questions about the limits of Bayesianism. First, I will show that one cannot strengthen the positive result by restricting the evidence to so-called “certain evidence”. Secondly, strengthening the result by restricting the partitions—as parts of one’s evidence—to (...) Jeffrey-independent partitions requires additional constraints on one’s evidence to preserve its commutativity. So, my results provide additional grounds for caution and support for the limitations of Bayesian learning. (shrink)

The article offers a rigorous explication of the intuitive notion of verisimilitude, I.E., Of the distance of a theory from the truth. The proposal is defended against charges of material inadequacy made by popper, Niniluoto, And miller.

Our sense of agency and ability to distinguish between intentional and accidental actions are fundamental for social interaction. They allow us to plan and perform joint actions and assign responsibility for our own actions and those of others. Research on the nature of agency and intentions has been very fruitful over the last few decades in philosophy, linguistics, and psychology. However, trully new discoveries could be made only when we engage in interdisciplinary discussions. This volume is the result of such (...) discussions. (shrink)

The Hanf number for a set S of sentences in \ is the least infinite cardinal \ such that for all \, if \ has models in all infinite cardinalities less than \, then it has models of all infinite cardinalities. Friedman asked what is the Hanf number for Scott sentences of computable structures. We show that the value is \. The same argument proves that \ is the Hanf number for Scott sentences of hyperarithmetical structures.