The language of the basic logic of proofs extends the usual propositional language by forming sentences of the sort x is a proof of F for any sentence F. In this paper a complete axiomatization for the basic logic of proofs in Heyting Arithmetic HA was found.

In 1933 Godel introduced a calculus of provability (also known as modal logic S4) and left open the question of its exact intended semantics. In this paper we give a solution to this problem. We find the logic LP of propositions and proofs and show that Godel's provability calculus is nothing but the forgetful projection of LP. This also achieves Godel's objective of defining intuitionistic propositional logic Int via classical proofs and provides a Brouwer-Heyting-Kolmogorov style provability semantics for Int which (...) resisted formalization since the early 1930s. LP may be regarded as a unified underlying structure for intuitionistic, modal logics, typed combinatory logic and λ-calculus. (shrink)

We describe a general logical framework, Justification Logic, for reasoning about epistemic justification. Justification Logic is based on classical propositional logic augmented by justification assertions t: F that read t is a justification for F. Justification Logic absorbs basic principles originating from both mainstream epistemology and the mathematical theory of proofs. It contributes to the studies of the well-known Justified True Belief vs. Knowledge problem. We state a general Correspondence Theorem showing that behind each epistemic modal logic, there is a (...) robust system of justifications. This renders a new, evidence-based foundation for epistemic logic. As a case study, we offer a resolution of the GoldmanRed Barns in Justification Logic. Furthermore, we formalize the well-known Gettier example and reveal hidden assumptions and redundancies in Gettier’s reasoning. (shrink)

In this paper individual proofs are integrated into provability logic. Systems of axioms for a logic with operators “A is provable” and “p is a proof of A” are introduced, provided with Kripke semantics and decision procedure. Completeness theorems with respect to the arithmetical interpretation are proved.

Justification Logic provides an axiomatic description of justifications and delegates the question of their nature to semantics. In this note, we address the conceptual issue of the logical type of justifications: we argue that justifications in the logical setting are naturally interpreted as sets of formulas which leads to a class of epistemic models that we call modular models . We show that Fitting models for Justification Logic naturally encode modular models and can be regarded as convenient pre-models of the (...) former. (shrink)

In this paper, we provide a semantic analysis of the well-known knowability paradox stemming from the Church–Fitch observation that the meaningful knowability principle /all truths are knowable/, when expressed as a bi-modal principle F --> K♢F, yields an unacceptable omniscience property /all truths are known/. We offer an alternative semantic proof of this fact independent of the Church–Fitch argument. This shows that the knowability paradox is not intrinsically related to the Church–Fitch proof, nor to the Moore sentence upon which it (...) relies, but rather to the knowability principle itself. Further, we show that, from a verifiability perspective, the knowability principle fails in the classical logic setting because it is missing the explicit incorporation of a hidden assumption of /stability/: ‘the proposition in question does not change from true to false in the process of discovery.’ Once stability is taken into account, the resulting /stable knowability principle/ and its nuanced versions more accurately represent verification-based knowability and do not yield omniscience. (shrink)

Logical theories for representing knowledge are often plagued by the so-called Logical Omniscience Problem. The problem stems from the clash between the desire to model rational agents, which should be capable of simple logical inferences, and the fact that any logical inference, however complex, almost inevitably consists of inference steps that are simple enough. This contradiction points to the fruitlessness of trying to solve the Logical Omniscience Problem qualitatively if the rationality of agents is to be maintained. We provide a (...) quantitative solution to the problem compatible with the two important facets of the reasoning agent: rationality and resource boundedness. More precisely, we provide a test for the logical omniscience problem in a given formal theory of knowledge. The quantitative measures we use are inspired by the complexity theory. We illustrate our framework with a number of examples ranging from the traditional implicit representation of knowledge in modal logic to the language of justification logic, which is capable of spelling out the internal inference process. We use these examples to divide representations of knowledge into logically omniscient and not logically omniscient, thus trying to determine how much information about the reasoning process needs to be present in a theory to avoid logical omniscience. (shrink)

The paper proves a predicate version of Solovay's well-known theorem on provability interpretations of modal logic: If a closed modal predicate-logical formula R is not valid in some finite Kripke model, then there exists an arithmetical interpretation f such that $PA \nvdash fR$ . This result implies the arithmetical completeness of arithmetically correct modal predicate logics with the finite model property (including the one-variable fragments of QGL and QS). The proof was obtained by adding "the predicate part" as a specific (...) addition to the standard Solovay construction. (shrink)

In this paper the modal operator "x is provable in Peano Arithmetic" is incorporated into first-order theories. A provability extension of a theory is defined. Presburger Arithmetic of addition, Skolem Arithmetic of multiplication, and some first order theories of partial consistency statements are shown to remain decidable after natural provability extensions. It is also shown that natural provability extensions of a decidable theory may be undecidable.

We introduce reference structures — a basic mathematical model of a data organization capable of storing and utilizing information about its addresses. A propositional labeled modal language is used as a specification and programming language for reference structures; the satisfiability algorithm for modal language gives a method of building and optimizing reference structures satisfying a given formula. Corresponding labeled modal logics are presented, supplied with cut free axiomatizations, completeness and decidability theorems are proved. Initialization of typed variables in some programming (...) languages is presented as an example of a reference structure building. (shrink)

ABSTRACT In 1933 Gödel introduced an axiomatic system, currently known as S4, for a logic of an absolute provability, i.e. not depending on the formalism chosen ([God 33]). The problem of finding a fair provability model for S4 was left open. The famous formal provability predicate which first appeared in the Gödel Incompleteness Theorem does not do this job: the logic of formal provability is not compatible with S4. As was discovered in [Art 95], this defect of the formal provability (...) predicate can be bypassed by replacing hidden quantifiers over proofs by proof polynomials in a certain finite basis. The resulting Logic of Proofs enjoys a natural arithmetical semantics and provides an intended provability model for S4, thus answering a question left open by Gödel in 1933. Proof polynomials give an intended semantics for some other constructions based on the concept of provability, including intuitionistic logic with its Brouwer- Heyting- Kolmogorov interpretation, ?-calculus and modal ?-calculus. In the current paper we demonstrate how the intuitionistic propositional logic Int can be directly realized by proof polynomials. It is shown, that Int is complete with respect to this proof realizability. (shrink)

Justification Logic is a family of epistemic logical systems obtained from modal logics of knowledge by adding a new type of formula t:F, which is read t is a justification for F. The principal epistemic modal logic S4 includes Tarski’s well-known topological interpretation, according to which the modality 2X is read the Interior of X in a topological space (the topological equivalent of the ‘knowable part of X’). In this paper, we extend Tarski’s topological interpretation from S4 to Justification Logic (...) systems with both modality and justification assertions. The topological semantics interprets t:X as a reachable subset of X (the topological equivalent of ‘test t confirms X’). We establish a number of soundness and completeness results with respect to Kripke topology and the real topology for S4-based systems of Justification Logic. (shrink)

Poses of the World develops a theory of the pluralistic coexistence of politics with aesthetic, scientific, ethical and economic procedures that have sought to influence, dominate or even replace politics. We are accustomed to saying that everything is political. It is true that politics has throughout history ventured into the domains that used to be non-political, be they art, science or economy. However, rather than being totally dominated by politics, our societies are marked by the coexistence of diverse procedures, whose (...) logics are distinct but nonetheless remain in contact, ranging from frontal conflict to lasting syntheses. This book develops a theory of this pluralistic coexistence. It builds upon the findings of the first two volumes of Void Universalism to outline an account of pluralism that affirms the incommensurable character of the procedures that regulate the manners of our being and acting in the world. Neither reducible to nor insulated from each other, politics, ethics, art, economy, science and numerous other procedures persist in errancy without ever cohering into any overarching unity. The book demonstrates how the abandonment of the aspiration for such coherence opens up new perspectives on the key sociopolitical debates of our time, from the critique of neoliberalism to concerns over cancel culture. Systematic and accessible, this volume will be of interest to students and scholars of political science, philosophy, sociology, anthropology and cultural studies as well a wider readership beyond academia. (shrink)

The book represents a comprehensive account of the principles of the philosophy of the pseudoabsolute and is intended for readers interested in the issues of theoretical philosophy. It is also meant for a wide range of readers interested in the relative and absolute nature of human mentality.

This paper introduces a theory of ownership that is rooted in Israel Kirzner’s theory of entrepreneurship – The Entrepreneurial Theory of Ownership. Its central idea is that natural resources are not available to us automatically as other approaches to justice implicitly assume. Before we can use a resource, we need to do preparatory work in the form of making an entrepreneurial judgement on it. This fact, as I argue, makes it possible to put private ownership as a natural right on (...) a firm normative ground and answer many traditional challenges to private property. (shrink)

The paper aims to present a critical analysis of the phenomenon and notion of exceptionalism in bioethics. The authors demonstrate that exceptionalism pertains to phenomena that are not (yet) entirely familiar to us and could potentially bear risks regarding their regulation. After an overview of the state of the art, we briefly describe the origins and evolution of the concept, compared to exception and exclusion. In the second step, they look at the overall development debates on genetic exceptionalism, compared to (...) other bioethical debates on exceptionalism, before presenting a detailed analysis of a specific case of early regulation of genetic screening. In the last part, the authors explain the historical background behind the connection between exceptionalism and exclusion in these debates. Their main conclusion is that while the initial stage of the discussion is shaped by the concept of exceptionalism and awareness of risks of exclusion, the later development centers around exceptions that are needed in detailed regulatory procedures. (shrink)

Historical entitlement theories of property rights, which claim that individuals can acquire moral property rights over natural resources by appropriating them, traditionally face a strong objection: it is widely implausible that a single individual can unilaterally impose duties on everyone around him and yet, apparently, this is exactly what such theories allow. In this essay, I argue that the same problem appears in all other theories of distributive justice and if this problem was a reason to reject historical entitlement theories, (...) it would also be a reason to reject all rival theories. Which means that as long, as one is committed to any theory of distributive justice at all, she, at the risk of inconsistency, cannot rely on the aforementioned objection to criticize historical entitlement theories. (shrink)

This article examines a still contentious question: how conservative and liberal elements are combined in Boris N. Chicherin’s worldview and political doctrine. It considers several points of view...

Why does the theory of law have such a significant role in Russian liberalism, and how is this related to the state of the legal system in Russia and to the public’s legal consciousness? This intro...

In this paper the philosophical ideology of eclecticism of Modern times is considered, especially as it has been formulated byJ. Ch.Sturm, and assessment of its contribution to development of philosophical and scientific thought is given. The need of differentiation of eclecticism, syncretism and conciliatorics is proved. Eclecticism is characterized as a progressive for its time current. The decisive impact eclecticism on formation of new scientific outlook is emphasized.

The article proceeds from the concept of understanding local government in Russia as a projection of the potestar (pre-state) organization of public life, which transforms under the dominance of methods of state organization of public life, but retains its influence as the essential core of political and social interaction between people. The existing complex «state-municipal» mechanism for exercising power at the local level largely determines the forms and nature of political actors’ interaction at the regional level. State authorities, which are (...) focused on the totality of their own administrative influences, have not yet succeeded in fully integrating local self-government into the general public space of responsibility for powers, since local power is unbuilt initially on the principles of autogenesis, autochthony and autonomy. The current situation contributes to the archaicism of a part of social relations. For some time now, to work in the multidimensional reality of society, the authorities have begun to need analytical models to understand what is happening. As an explanatory theoretical basis for the modes of existence of local authorities developed and described by the author in the current stage of development of Russian statehood, a modal methodology is used, supplemented by the results of constructing model-oriented political ontologies, which reflect the aggregates of the layers and actors of the municipal sphere of sociopolitical reality at the regional level that are actually and actively present in the Russian society. The author is interested in searching the patterns that operate in the environment created and cultivated by the organizational and activity efforts of state structures against the background of sociocultural and other characteristics inherent in the regions. Possible working models for the needs of public administration arising from the modes offered by the author are still under development, since the reform of constitutional rules proposed by the country’s leadership raises the question of new forms of organizing the continuum of coexistence and interaction of local and state authorities in Russia. The article outlines the main research lines that indicate a number of features and reference points of the author’s approach in understanding the relationship between local government and municipal government, which may serve as an occasion for a new circle of discussions of specialists interested in the prospects for the development of political potential in the Russian municipal environment. (shrink)