On the autological character of diagonalizable algebras

Summary Let be the first order theory of diagonalizable algebras. We define a bijection from the atomic formulas of (identities) to the open formulas of . is an algebraic analogous of ≒. We prove that , ^-1 preserve the validity.The algebraization of the theories which express TheorSee the precedent papers with the same subtitle.Allatum est die 21 Julii 1975     

On the logic of conscious belief

In this paper we are discussing a version of propositional belief logic, denoted by LB, in which so-called axioms of introspection (B BB and B B B) are added to the usual ones. LB is proved to be sound and complete with respect to Boolean algebras equipped with proper filters (Theorem 5). Interpretations in classical theories (Theorem 4) are also considered. A few modifications of LB are further dealt with, one of which turns out to be S5.     

On Neat Reducts of Algebras of Logic

SC , CA , QA and QEA stand for the classes of Pinter's substitution algebras, Tarski's cylindric algebras, Halmos' quasipolyadic algebras, and quasipolyadic equality algebras of dimension , respectively. Generalizing a result of Németi on cylindric algebras, we show that for K {SC, CA, QA, QEA} and ordinals < , the class Nr K of -dimensional neat reducts of -dimensional K algebras, though closed under taking homomorphic images and products, is not closed under forming subalgebras (i.e. is not a variety) if and only if > 1.From this it easily follows that for 1 < < , the operation of forming -neat reducts of algebras in K does not commute with forming subalgebras, a notion to be made precise.We give a contrasting result concerning Halmos' polyadic algebras (with and without equality). For such algebras, we show that the class of infinite dimensional neat reducts forms a variety.We comment on the status of the property of neat reducts commuting with forming subalgebras for various reducts of polyadic algebras that are also expansions of cylindric-like algebras. We try to draw a borderline between reducts that have this property and reducts that do not.Following research initiated by Pigozzi, we also emphasize the strong tie that links the (apparently non-related) property of neat reducts commuting with forming subalgebras with proving amalgamation results in cylindric-like algebras of relations. We show that, like amalgamation, neat reducts commuting with forming subalgebras is another algebraic expression of definability and, accordingly, is also strongly related to the well-known metalogical properties of Craig, Beth and Robinson in the corresponding logics.     

Some modifications of Scott's theorem on injective spaces

D. Scott in his paper [5] on the mathematical models for the Church-Curry -calculus proved the following theorem.A topological space X. is an absolute extensor for the category of all topological spaces iff a contraction of X. is a topological space of Scott's open sets in a continuous lattice.In this paper we prove a generalization of this theorem for the category of , -closure spaces. The main theorem says that, for some cardinal numbers , , absolute extensors for the category of , -closure spaces are exactly , -closure spaces of , -filters in , >-semidistributive lattices (Theorem 3.5).If = and = we obtain Scott's Theorem (Corollary 2.1). If = 0 and = we obtain a characterization of closure spaces of filters in a complete Heyting lattice (Corollary 3.4). If = 0 and = we obtain a characterization of closure space of all principial filters in a completely distributive complete lattice (Corollary 3.3).     

A New Representation Theorem for Contranegative Deontic Logic

The logic of an ought operator O is contranegative with respect to an underlying preference relation if it satisfies the property Op & (¬p)(¬q) Oq. Here the condition that is interpolative ((p (pq) q) (q (pq) p)) is shown to be necessary and sufficient for all -contranegative preference relations to satisfy the plausible deontic postulates agglomeration (Op & OqO(p&q)) and disjunctive division (O(p&q) Op Oq).     

Varieties of Monadic Heyting Algebras. Part III

This paper is the concluding part of [1] and [2], and it investigates the inner structure of the lattice (MHA) of all varieties of monadic Heyting algebras. For every n , we introduce and investigate varieties of depth n and cluster n, and present two partitions of (MHA), into varieties of depth n, and into varieties of cluster n. We pay a special attention to the lower part of (MHA) and investigate finite and critical varieties of monadic Heyting algebras in detail. In particular, we prove that there exist exactly thirteen critical varieties in (MHA) and that it is decidable whether a given variety of monadic Heyting algebras is finite or not. The representation of (MHA) is also given. All these provide us with a satisfactory insight into (MHA). Since (MHA) is dual to the lattice NExtMIPC of all normal extensions of the intuitionistic modal logic MIPC, we also obtain a clearer picture of the lattice structure of intuitionistic modal logics over MIPC.     

A reduction rule for Peirce formula

A reduction rule is introduced as a transformation of proof figures in implicational classical logic. Proof figures are represented as typed terms in a -calculus with a new constant P ⁽⁽⁾⁾. It is shown that all terms with the same type are equivalent with respect to -reduction augmented by this P-reduction rule. Hence all the proofs of the same implicational formula are equivalent. It is also shown that strong normalization fails for P-reduction. Weak normalization is shown for P-reduction with another reduction rule which simplifies of (( ) ) into an atomic type.This work was partially supported by a Grant-in-Aid for General Scientific Research No. 05680276 of the Ministry of Education, Science and Culture, Japan and by Japan Society for the Promotion of Science. Hiroakira Ono     

Независимость одной системы аксиом и правила вывода пропозиционального исчисления

- Allatum est die 5 Martii 1970     

Decision problems for classes of diagonalizable algebras

We make use of a Theorem of Burris-McKenzie to prove that the only decidable variety of diagonalizable algebras is that defined by 0=1. Any variety containing an algebra in which 01 is hereditarily undecidable. Moreover, any variety of intuitionistic diagonalizable algebras is undecidable.     

The ω-rule

We prove that all proofs in -logic (a first order logic with -rule added) in which -rule is used finitely many times can be turned into proofs in which the -rule is used at most one time. Next, we prove that the word finitely above cannot be changed by the word infinitely.     

Kenneth Strike on Liberalism,Citizenship and the Private Interest in Schooling

After indicating a number of points of agreement with the argument 0eveloped by Kenneth Strike in his article Liberalism, Citizenship and the Private Interest in Schooling, this article identifies and explores a number of queries and criticisms which arise in relation to that argument. These queries and criticisms relate especially to the nature and extent of the expansiveness involved in Strike's conception of public or common educational influence, and to the implications and justification of the claim that private educational interests enjoy a greater salience and recognition on Strike's view of public or common educational influence than on some alternative views.     

Self and others in “private language”

The aim of this paper is to restore the interdependent or complementary relationship between self and others against the universalistic one (as I call it) that Kant, for example, once insisted on, by reexamining the concept of so-called private language. I shall consider some views in speech act theory and pragmatics, since there has often been discussion about such a private occurrence as the speaker's sincerity. For example, Jürgen Habermas situates it in the speaker's internal nature as will be seen later. In my opinion, alter ego is an ego because we can empathize (einfühlen) with it, and yet it is alter ego because it has some private experiences which we cannot perfectly comprehend.     

⊃E is Admissible in “true” relevant arithmetic

The system R## of true relevant arithmetic is got by adding the -rule Infer xAx from A0, A1, A2, .... to the system R# of relevant Peano arithmetic. The rule E (or gamma) is admissible for R##. This contrasts with the counterexample to E for R# (Friedman & Meyer, Whither Relevant Arithmetic). There is a Way Up part of the proof, which selects an arbitrary non-theorem C of R## and which builds by generalizing Henkin and Belnap arguments a prime theory T which still lacks C. (The key to the Way Up is a Witness Protection Program, using the -rule.) But T may be TOO BIG, whence there is a Way Down argument that produces a better theory TR, such that R## TR T. (The key to the Way Down is a Metavaluation, on which membership in T is combined with ordinary truth-functional conditions to determine TR.) The result is a theory that is Just Right, whence it never happens that A C and A are theorems of R## but C is a non-theorem.     

Proof-Theoretic Modal PA-Completeness I: A System-Sequent Metric

This paper is the first of a series of three articles that present the syntactic proof of the PA-completeness of the modal system G, by introducing suitable proof-theoretic objects, which also have an independent interest. We start from the syntactic PA-completeness of modal system GL-LIN, previously obtained in [7], [8], and so we assume to be working on modal sequents S which are GL-LIN-theorems. If S is not a G-theorem we define here a notion of syntactic metric d(S, G): we calculate a canonical characteristic fomula H of S (char(S)) so that _G H (S) and _GL-LIN H, and the complexity of H gives the distance d(S, G) of S from G. Then, in order to produce the whole completeness proof as an induction on this d(S, G), we introduce the tree-interpretation of a modal sequent Q into PA, that sends the letters of Q into PA-formulas describing the properties of a GL-LIN-proof P of Q: It is also a d(*, G)-metric linked interpretation, since it will be applied to a proof-tree T of H with H = char(S) and ( H) = d(S, G).     

In and behind a Lenneberg paradigm

Lenneberg suggested that a chimpanzee's linguistic ability could be tested by presenting sentences containing two prepositional phrases joined by a conjunction. This would involve joining two semantic propositions, and thus represents a more complex test of chimpanzee syntactic competence than previously attempted. Jane, a five year-old language trained chimpanzee, was tested on her ability to both produce and comprehend sentences involving a preposition (in or behind) and a conjunction (and). The results from production and comprehension were substantially the same. Jane showed the ability to appropriately deploy and, behind and in, but displayed very little flexibility in their use. It is suggested that a chimpanzee may be able to learn some rules of syntax but is not able to be creative with that syntax.     

Axiomatizing logics closely related to varieties

Let V be a s.f.b. (strongly finitely based, see below) variety of algebras. The central result is Theorem 2 saying that the logic defined by all matrices (A, d) with d A V is finitely based iff the A V have 1^st order definable cosets for their congruences. Theorem 3 states a similar axiomatization criterion for the logic determined by all matrices (A, ^A), A V, a term which is constant in V. Applications are given in a series of examples.     

Fragmentation and re-integration of experience

Secular and religious counselors require a model of psychotherapy that conceptualizes human beings as conscious, goal-seeking entities. Such a model, based on the construct being in one's own world, is sketched in broad outline in this essay. The building blocks for the model are the intentional modes that lie at the heart of the self-world dialectic in which we live our lives. It is demonstrated how these intentional modes are organized into a gestalt-like whole referred to as the existential gestalt. From the diagram of the existential gestalt the concepts of intentional clarity and modal congruence are derived. These concepts enable us to understand the processes of the fragmentation and re-integration of experience that lie at the heart of psychotherapy. Inclusiveness and purposefulness, two additional factors that are important for assessing the adequacy of the existential gestalt, are also briefly touched upon.     

Discrete tense logic with infinitary inference rules and systematic frame constants: A Hilbert-style axiomatization

The paper deals with the problem of axiomatizing a system 1 of discrete tense logic, where one thinks of time as the set Z of all the integers together with the operations +1 (immediate successor) and -1 (immediate predecessor). 1 is like the Segerberg-Sundholm system W1 in working with so-called infinitary inference rules; on the other hand, it differs from W1 with respect to (i) proof-theoretical setting, (ii) presence of past tense operators and a now operator, and, most importantly, with respect to (iii) the presence in of so-called systematic frame constants, which are meant to hold at exactly one point in a temporal structure and to enable us to express the irreflexivity of such structures. Those frame constants will be seen to play a paramount role in our axiomatization of 1.The present contribution reports research done under the auspices of the Swedish Council for Research in the Humanities and the Social Sciences (HSFR), project On the Legal Concepts of Rights and Duties: an Analysis Based on Deontic and Causal Conditional Logic. I wish to thank the anonymous referee for his/her extremely patient and accurate revision work, and Krister Segerberg for his helpful suggestions.     

Murder in the family: An analysis of two Poe short stories

Learning to be possessed has been described elsewhere by the writer as a form of pathogenic relating begun when children are taught by adults that they will receive a lesser penalty for misbehavior if they can show they were not responsible, such as if it were caused by an evil agent or the Devil. It was suggested that learning to be possessed can be an underlying cause of psychopathology, the delusion of persecution in particular. Two short stories by the distinguished American writer Edgar Allan Poe are examined to develop the formulation of learning to be possessed, especially when it has passed to a delusion of persecution. Two propositions are offered: (1) Where it appears that a family member is murdered by a delusional assailant by accident, it is not an accident; and (2) the delusion of persecution entails a memory loss so that the murderer not only can claim lack of personal responsibility for the act, but also spares himself the guilt of having broken a fundamental taboo. Further comparison is made between learning to be possessed as a cause of delusion, and the psychoanalytic theory in which the defense mechanism of projection is central. In the latter theory, interpretation of the delusion is critical; whereas in the former, interpretation is counterproductive because it merely reinforces the delusion.Probably a note of appreciation is due the writer's daughter Cary, who at age 14 is an expert at badgering her father for help with homework assignments. For several weeks the writer was alternatively pestered and cajoled to help Cary with her Poe Project for high school English which required an essay analyzing the work of a great American writer denigrated by the author as weird by his recollection formed decades earlier. Cary's persistence required the author to consider Poe anew, to recognize his unwarranted earlier prejudice, and to recognize that Poe offered him a gift of understanding regarding a topic about which the author had been thinking for several years, namely that form of pathogenic relating named learning to be possessed.     

The elegant solution to the problem of impotence

Although most therapists are committed to debunking the dual myths that sex requires an erection and that sex equals intercourse, sex researchers continue to use successful intercourse as a primary dependent variable. It is here asserted that RET therapists would do well to approach the problem of erectile dysfunction from a more elegant philosophical perspective. The treatment approach outlined here is aimed at reducing client disturbance as well as increasing sexual satisfaction rather than at simply helping the client to regain his potency.