Within a weak subsystem of second-order arithmetic , that is -conservative over , we reformulate Kreisel's proof of the Second Incompleteness Theorem and Boolos' proof of the First Incompleteness Theorem.

Akama et al. [1] systematically studied an arithmetical hierarchy of the law of excluded middle and related principles in the context of first-order arithmetic. In that paper, they first provide a prenex normal form theorem as a justification of their semi-classical principles restricted to prenex formulas. However, there are some errors in their proof. In this paper, we provide a simple counterexample of their prenex normal form theorem [1, Theorem 2.7], then modify it in an appropriate way which still serves (...) to largely justify the arithmetical hierarchy. In addition, we characterize a variety of prenex normal form theorems by logical principles in the arithmetical hierarchy. The characterization results reveal that our prenex normal form theorems are optimal. For the characterization results, we establish a new conservation theorem on semi-classical arithmetic. The theorem generalizes a well-known fact that classical arithmetic is $\Pi _2$ -conservative over intuitionistic arithmetic. (shrink)

We shall prove the second incompleteness theorem via Kolmogorov complexity.

In this paper, a semantics for predicate logics without the contraction rule will be investigated and the completeness theorem will be proved. Moreover, it will be found out that our semantics has a close connection with Beth-type semantics.

In this paper, I show that the availability of what some authors have called the weak reading and the strong reading of donkey sentences with relative clauses is systematically related to monotonicity properties of the determiner. The correlation is different from what has been observed in the literature in that it concerns not only right monotonicity, but also left monotonicity (persistence/antipersistence). I claim that the reading selected by a donkey sentence with a double monotone determiner is in fact the one (...) that validates inference based on the left monotonicity of the determiner. This accounts for the lack of strong reading in donkey sentences with MON determiners, which have been neglected in the literature. I consider the relevance of other natural forms of inference as well, but also suggest how monotonicity inference might play a central role in the actual process of interpretation. The formal theory is couched in dynamic predicate logic with generalized quantifiers. (shrink)

We systematically study conservation theorems on theories of semi-classical arithmetic, which lie in-between classical arithmetic $\mathsf {PA}$ and intuitionistic arithmetic $\mathsf {HA}$. Using a generalized negative translation, we first provide a structured proof of the fact that $\mathsf {PA}$ is $\Pi _{k+2}$ -conservative over $\mathsf {HA} + {\Sigma _k}\text {-}\mathrm {LEM}$ where ${\Sigma _k}\text {-}\mathrm {LEM}$ is the axiom scheme of the law-of-excluded-middle restricted to formulas in $\Sigma _k$. In addition, we show that this conservation theorem is optimal in the (...) sense that for any semi-classical arithmetic T, if $\mathsf {PA}$ is $\Pi _{k+2}$ -conservative over T, then ${T}$ proves ${\Sigma _k}\text {-}\mathrm {LEM}$. In the same manner, we also characterize conservation theorems for other well-studied classes of formulas by fragments of classical axioms or rules. This reveals the entire structure of conservation theorems with respect to the arithmetical hierarchy of classical principles. (shrink)

Savant syndrome and prime numbers Oliver Sacks reported that a pair of autistic twins had extraordinary number abilities and that they spontaneously generated huge prime numbers. Such abilities could contradict our understanding of human abilities. Sacks' report attracted widespread attention, and several researchers speculated theoretically. Unfortunately, most of the explanations in the literature are wrong. Here a correct explanation on prime number identification is provided. Fermat's little theorem is implemented in spreadsheet. Also, twenty years after the report, questionable aspects were (...) found in it. Extreme abilities became dubious. One possibility for the less extreme abilities is incomplete trial division. (shrink)

It is well known that Gödel’s incompleteness theorems hold for ∑1-definable theories containing Peano arithmetic. We generalize Gödel’s incompleteness theorems for arithmetically definable theories. First, we prove that every ∑n+1-definable ∑n-sound theory is incomplete. Secondly, we generalize and improve Jeroslow and Hájek’s results. That is, we prove that every consistent theory having ∏n+1set of theorems has a true but unprovable ∏nsentence. Lastly, we prove that no ∑n+1-definable ∑n-sound theory can prove its own ∑n-soundness. These three results are generalizations of Rosser’s (...) improvement of the first incompleteness theorem, Gödel’s first incompleteness theorem, and the second incompleteness theorem, respectively. (shrink)

It is proved that for any k, the class of classical categorial grammars that assign at most k types to each symbol in the alphabet is learnable, in the Gold (1967) sense of identification in the limit from positive data. The proof crucially relies on the fact that the concept known as finite elasticity in the inductive inference literature is preserved under the inverse image of a finite-valued relation. The learning algorithm presented here incorporates Buszkowski and Penn's (1990) algorithm for (...) determining categorial grammars from input consisting of functor-argument structures. (shrink)

We systematically study several principles and give a principle which is weaker than disjunctive Markov’s principle. We also show that the principle is underivable and strictly weaker than MP∨ in certain extensions of the system EL of elementary analysis.

Translated text is chapt. 7, pt. 2 of Kirisutokyō no benshō.

We develop a general algebraic and proof-theoretic study of substructural logics that may lack associativity, along with other structural rules. Our study extends existing work on substructural logics over the full Lambek Calculus [34], Galatos and Ono [18], Galatos et al. [17]). We present a Gentzen-style sequent system that lacks the structural rules of contraction, weakening, exchange and associativity, and can be considered a non-associative formulation of . Moreover, we introduce an equivalent Hilbert-style system and show that the logic associated (...) with and is algebraizable, with the variety of residuated lattice-ordered groupoids with unit serving as its equivalent algebraic semantics. Overcoming technical complications arising from the lack of associativity, we introduce a generalized version of a logical matrix and apply the method of quasicompletions to obtain an algebra and a quasiembedding from the matrix to the algebra. By applying the general result to specific cases, we obtain important logical and algebraic properties, including the cut elimination of and various extensions, the strong separation of , and the finite generation of the variety of residuated lattice-ordered groupoids with unit. (shrink)

We provide a fine‐grained analysis on the relation between König's lemma, weak König's lemma, and the decidable fan theorem in the context of constructive reverse mathematics. In particular, we show that double negated variants of König's lemma and weak König's lemma are equivalent to double negated variants of the general decidable fan theorem and the binary decidable fan theorem, respectively, over a nearly intuitionistic system containing a weak countable choice only. This implies that the general decidable fan theorem is not (...) equivalent to the binary decidable fan theorem in the absence of a strong countable choice. In addition, we introduce a principle which fills the gap between König's lemma and weak König's lemma, and show that König's lemma is equivalent to weak König's lemma plus this principle. We also solve several problems arising from the investigation. (shrink)

Estrogen receptor α (ERα) is a ligand‐dependent transcription factor that regulates the expression of estrogen‐responsive genes. Approximately 70% of patients with breast cancer are ERα positive. Estrogen stimulates cancer cell proliferation and contributes to tumor progression. Endocrine therapies, which suppress the ERα signaling pathway, significantly improve the prognosis of patients with breast cancer. However, the development of de novo or acquired endocrine therapy resistance remains a barrier to breast cancer treatment. Therefore, understanding the regulatory mechanisms of ERα is essential to (...) overcome the resistance to treatment. This review focuses on the regulation of ERα expression, including copy number variation, epigenetic regulation, transcriptional regulation, and stability, as well as functions from the point of view post‐translational modifications. (shrink)

没後20年、いま必要な歴史に裏打ちされた予見力、現実政治に提言する率直さ、道義性と理想主義。.

Prediction is essential for the efficiency of many cognitive processes; however, this process is not always perfect. Predictive coding theory suggests that the brain generates and updates a prediction to respond to an upcoming event. Although an electrophysiological index of prediction, the stimulus preceding negativity, has been reported, it remains unknown whether the SPN reflects the prediction accuracy, or whether it is associated with the prediction error, which corresponds to a mismatch between a prediction and an actual input. Thus, the (...) present study aimed to investigate this question using electroencephalography. Participants were asked to predict the original pictures from pictures that had undergone different levels of pixelation. The SPN amplitude was affected by the level of pixelation and correlated with the subjective evaluation of the prediction accuracy. Furthermore, late positive components were negatively correlated with SPN. These results suggest that the amplitude of SPN reflects the prediction accuracy; more accurate prediction increases the SPN and reduces the prediction error, resulting in reduced LPC amplitudes. (shrink)

In this collection on the Kyoto School of Philosophy, the author offers the reader Tanabe's religious philosophy, but also, and for the first time, his ...

Tanabe Hajime, the Kyoto School philosopher of modern Japan, proposes a new idea of the relationship between religion and politics in terms of the triadic logic of species that is motivated by the religious moment of repentance. Even the state existence has the inherently radical evil as in the case of the individual person, due to its duality of the species level of being. This means that the state existence is on the way of actualization of the genus like universality, (...) while always involving in the regression into the past substrative being which prevents it from realizing its own universality. In other words, the state existence is not absolute as such but rather a balanced being between ideality and reality, absolute and relative. This entails that politics is in need of perpetual reformation in connection with the religious act of repentance for sin and evil deeply lurked in human beings from time immemorial. Tanabe’s Logic of Species as the dialectic elucidates the negative mediation of politics and religion from the metanoetic perspective and sheds a new light on the relation of world religion and politics today. (shrink)

The historical origins of the Kyoto School of Philosophy of modern Japan, represented by Kitaro Nishida and Hajime Tanabe, may be derived from both the ancient Chinese idea of Change and the ancient Indian Upanishadic idea of the mutual identity of Brahman and Atman. The ancient Chinese idea of Change signifies change as well as non-change, and even their dialectical unification. Both origins are structured by the self-identity of the opposed in logic, and these historical prototypes have been developed into (...) the various forms of Confucian, Taoist, and Buddhist philosophy. The notion of Nothingness or Emptiness rather than Being has been set up as the fundamental principle. The principle of Nothingness as ultimate reality has been connected with the logic of self-identity of theopposed, and this is evident in Nishida’s concept of the self-identity in absolute contradistinction that is equivalent to the Place of Absolute Nothingness. Even though Nishida’s idea of Place is directly and explicitly influenced by the ancient Greek idea of Topos, it has indirectly and implicitly been affected by the traditional agricultural society as well, in which the land is regarded as the self-identical substratum despite the cyclic time of the four-seasons change. The ancient Chinese idea of Change also reflects the agricultural society in which the cyclic time plays an important role on the basis of the unchanging self-identical land as the underlying substratum. Nishida succeeds in establishing the new logical expression of Eastern traditional thought, deeply hidden in consciousness, in relation toWestern philosophy. The uniqueness of Nishida’s idea of Place may have its main source in the traditional agricultural background, and in this sense his way of thinking may be rural in character. On the other hand, Tanabe, though following Nishida at first, turns to making criticism of the mentor with the establishment of the triadic logic of species as the dialectic, which is characterized by the perpetual self-negating conversion in action. In contrast to Nishida, Tanabe represents the urban type of thinking, which is in pursuit of transforming in life. While Nishida’s idea of Absolute Nothingness has an affinity with the ancient Chinese philosopher Laotzu’s idea of Nothingness from and into which every entity comes and goes, Tanabe’s concept of Absolute Nothingness as the principle ofconversion is more closed to the Buddhist idea of sunyata, i.e., Emptiness, which is devoid of any substance in itself. As regards evil, the difference between them is obvious in that for Nishida evil and time or history disappear into the ultimate horizon or place of Nothingness with the tendency toward a kind of monism of goodness, whereas for Tanabe evil copes with goodness and retains its own status throughout, never being reduced to the opposed. Even if so, both of them, however, fail to construct a philosophy of history from the epochal or durational viewpoint, compared to Heidegger and Jaspers. (shrink)

On sait que Platon fait grand cas des êtres intelligibles en instaurant la théorie des Idées. Mais il n’est pas approprié de le considérer comme penseur qui néglige le rôle de l’apparence sensible. Ce philosophe demeure très sensible à la modalité par laquelle les phénomènes apparaissent dans le champ de notreperception. En distinguant deux types d’apparence : image et simulacre, il donne à l’image le rôle d’intermédiaire actif entre le sensible et l’intelligible. L’examen des modalités des actions humaines qui reçoivent (...) et créent des images, nous aide à voir comment Platon intègre la fonction des images dans la structure de sa philosophie. La réception et la création des images sont étroitement reliées et synthétisées pour former le système original de Platon, système dans lequel le fondement de la théorie des Idées relève d’un certain dynamisme de l’action humaine. Dans la recherche relative à la modalité de réception et de création des images, je porte mon attention sur l’usage platonicien du terme tupos qui exprime le principe de la conformité de l’image et de son modèle.Notamment dans la théorie de la formation des futurs gardiens de la cité idéale, le tupos fonctionne, comme un principe qui réglemente et oriente à plusieurs niveaux les activités de la mimèsis et de la poièsis qui portent sur les images. La réflexion sur cette fonction conductrice. (shrink)

This article challenges claims that the Japanese neologism shūkyō lacked an established nature prior to the twentieth century and had little to do with experiences of the urban masses. It accordingly problematizes the term as a largely legal concept, highlighting historical newspapers as underutilized sources that offer insight into Meiji popular discourse and attendant conceptualizations of “religion.” This article endorses a shift in both our chronological understanding of shūkyō’s conceptual history as well as its sociocultural mobility. By expanding the milieu (...) understood as being familiar with debates on a range of “religious” issues, this article thereby offers a counter-narrative in which regular use of shūkyō begins to clearly emerge from the mid-1880s, exponentially increasing with the following decades. (shrink)

One of the primary views on our supposed obligation towards our descendants in the context of environmental problems invokes the idea of the rights of future generations. A growing number of authors also hold that the descendants of those victimized by historical injustices, including colonialism and slavery, have the right to demand financial reparations for the sufferings of their distant ancestors. However, these claims of intergenerational rights face theoretical difficulties, notably the non-identity problem. To circumvent this problem in a relationship (...) between present and future generations, some rights theorists replace future individual rights with such collective rights. Others advance the threshold conception of harm in discussing intergenerational relationships in general. Despite the significant implications these revisionist views might have, few efforts have been made to scrutinize their solidity. To plug such a gap in the literature, this paper examines to what extent the collective understanding of intergenerational rights is pertinent. I also explore the virtues and drawbacks of the threshold interpretation of harm. The paper concludes by suggesting that the motivation behind these and other versions of the rights theory suffers from the ambiguity of a traditional dichotomy between perfect and imperfect duties. (shrink)

Some formal properties of enriched systems of Lambek calculus with analogues of conjunction and disjunction are investigated. In particular, it is proved that the class of languages recognizable by the Lambek calculus with added intersective conjunction properly includes the class of finite intersections of context-free languages.