Results for ' ideals of compact sets'

973 found
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  1.  38
    A Gδ ideal of compact sets strictly above the nowhere dense ideal in the Tukey order.Justin Tatch Moore & Sławomir Solecki - 2008 - Annals of Pure and Applied Logic 156 (2):270-273.
    We prove that there is a -ideal of compact sets which is strictly above in the Tukey order. Here is the collection of all compact nowhere dense subsets of the Cantor set. This answers a question of Louveau and Veličković asked in [Alain Louveau, Boban Veličković, Analytic ideals and cofinal types, Ann. Pure Appl. Logic 99 171–195].
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  2.  40
    Trichotomies for Ideals of Compact Sets.É Matheron, S. Solecki & M. Zelený - 2006 - Journal of Symbolic Logic 71 (2):586 - 598.
    We prove several trichotomy results for ideals of compact sets. Typically, we show that a "sufficiently rich" universally Baire ideal is either $\Pi _{3}^{0}$-hard, or $\Sigma _{3}^{0}$-hard, or else a σ-ideal.
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  3.  28
    sets in σ-ideals generated by compact sets.Maya Saran - 2019 - Journal of Symbolic Logic 84 (2):781-797.
    Given a compact Polish space E and the hyperspace of its compact subsets , we consider Gδσ-ideals of compact subsets of E. Solecki has shown that any σ-ideal in a broad natural class of Gδ ideals can be represented via a compact subset of ; in this article we examine the behaviour of Gδ subsets of E with respect to the representing set. Given an ideal I in this class, we construct a representing set (...)
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  4.  43
    Murray G. Bell. Spaces of ideals of partial functions. Set theory and its applications, Proceedings of a conference held at York University, Ontario, Canada, Aug. 10–21,1987, edited by J. Streprāns and S. Watson, Lecture notes in mathematics, vol. 1401, Springer-Verlag, Berlin etc. 1989, pp. 1–4. - Alan Dow. Compact spaces of countable tightness in the Cohen model. Set theory and its applications, Proceedings of a conference held at York University, Ontario, Canada, Aug. 10–21,1987, edited by J. Streprāns and S. Watson, Lecture notes in mathematics, vol. 1401, Springer-Verlag, Berlin etc. 1989, pp. 55–67. - Peter J. Nyikos. Classes of compact sequential spaces. Set theory and its applications, Proceedings of a conference held at York University, Ontario, Canada, Aug. 10–21,1987, edited by J. Streprāns and S. Watson, Lecture notes in mathematics, vol. 1401, Springer-Verlag, Berlin etc. 1989, pp. 135–159. - Franklin D. Tall. Topological problems for set-theorists. Set theory and its appl. [REVIEW]Judith Roitman - 1991 - Journal of Symbolic Logic 56 (2):753-755.
    Reviewed Works:Murray G. Bell, J. Streprans, S. Watson, Spaces of Ideals of Partial Functions.Alan Dow, Compact Spaces of Countable Tightness in the Cohen Model.Peter J. Nyikos, Classes of Compact Sequential Spaces.Franklin D. Tall, Topological Problems for Set-Theorists.
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  5.  52
    Descriptive set theory of families of small sets.Étienne Matheron & Miroslav Zelený - 2007 - Bulletin of Symbolic Logic 13 (4):482-537.
    This is a survey paper on the descriptive set theory of hereditary families of closed sets in Polish spaces. Most of the paper is devoted to ideals and σ-ideals of closed or compact sets.
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  6.  19
    Orders of Indescribable Sets.Alex Hellsten - 2006 - Archive for Mathematical Logic 45 (6):705-714.
    We extract some properties of Mahlo’s operation and show that some other very natural operations share these properties. The weakly compact sets form a similar hierarchy as the stationary sets. The height of this hierarchy is a large cardinal property connected to saturation properties of the weakly compact ideal.
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  7.  20
    On Borel ideals.Fons van Engelen - 1994 - Annals of Pure and Applied Logic 70 (2):177-203.
    We show that a first category homogeneous zero-dimensional Borel set X can be embedded in as an ideal on ω if and only if X is homeomorphic to X × X if and only if X is Wadge-equivalent to X × X. Furthermore, we determine the Wadge classes of such X, thus giving a complete picture of the possible descriptive complexity of Borel ideals on ω. We also discuss the connection with ideals of compact sets.
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  8.  17
    Tukey order among ideals.Jialiang He, Michael Hrušák, Diego Rojas-Rebolledo & Sławomir Solecki - 2021 - Journal of Symbolic Logic 86 (2):855-870.
    We investigate the Tukey order in the class of Fσ ideals of subsets of ω. We show that no nontrivial Fσ ideal is Tukey below a Gδ ideal of compact sets. We introduce the notions of flat ideals and gradually flat ideals. We prove a dichotomy theorem for flat ideals isolating gradual flatness as the side of the dichotomy that is structurally good. We give diverse characterizations of gradual flatness among flat ideals using (...)
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  9.  43
    Analytic ideals and their applications.Sławomir Solecki - 1999 - Annals of Pure and Applied Logic 99 (1-3):51-72.
    We study the structure of analytic ideals of subsets of the natural numbers. For example, we prove that for an analytic ideal I, either the ideal {X (Ω × Ω: En X ({0, 1,…,n} × Ω } is Rudin-Keisler below I, or I is very simply induced by a lower semicontinuous submeasure. Also, we show that the class of ideals induced in this manner by lsc submeasures coincides with Polishable ideals as well as analytic P-ideals. We (...)
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  10.  79
    Analytic ideals.Sławomir Solecki - 1996 - Bulletin of Symbolic Logic 2 (3):339-348.
    §1. Introduction. Ideals and filters of subsets of natural numbers have been studied by set theorists and topologists for a long time. There is a vast literature concerning various kinds of ultrafilters. There is also a substantial interest in nicely definable ideals—these by old results of Sierpiński are very far from being maximal— and the structure of such ideals will concern us in this announcement. In addition to being interesting in their own right, Borel and analytic (...) occur naturally in the investigations of compact subsets of the space of all Baire class 1 functions on a Polish space, see [12, 18]. Also, certain objects associated with such ideals are of considerable interest and were quite extensively studied by several authors. Let us list here three examples; in all three of them I stands for an analytic or Borel ideal.1. The partial order induced by I on P: X ≥I Y iff X \ Y ϵ I and the partial order.2. Boolean algebras of the form P/I and their automorphisms.3. The equivalence relation associated with I: XEI Y iff X Δ ϵ I.In Section 4, we will have an opportunity to state some consequences of our results for equivalence relations as in 3. (shrink)
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  11.  44
    Forcing properties of ideals of closed sets.Marcin Sabok & Jindřich Zapletal - 2011 - Journal of Symbolic Logic 76 (3):1075 - 1095.
    With every σ-ideal I on a Polish space we associate the σ-ideal I* generated by the closed sets in I. We study the forcing notions of Borel sets modulo the respective σ-ideals I and I* and find connections between their forcing properties. To this end, we associate to a σ-ideal on a Polish space an ideal on a countable set and show how forcing properties of the forcing depend on combinatorial properties of the ideal. We also study (...)
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  12.  52
    Canonical structure in the universe of set theory: part one.James Cummings, Matthew Foreman & Menachem Magidor - 2004 - Annals of Pure and Applied Logic 129 (1-3):211-243.
    We start by studying the relationship between two invariants isolated by Shelah, the sets of good and approachable points. As part of our study of these invariants, we prove a form of “singular cardinal compactness” for Jensen's square principle. We then study the relationship between internally approachable and tight structures, which parallels to a certain extent the relationship between good and approachable points. In particular we characterise the tight structures in terms of PCF theory and use our characterisation to (...)
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  13.  56
    On splitting stationary subsets of large cardinals.James E. Baumgartner, Alan D. Taylor & Stanley Wagon - 1977 - Journal of Symbolic Logic 42 (2):203-214.
    Let κ denote a regular uncountable cardinal and NS the normal ideal of nonstationary subsets of κ. Our results concern the well-known open question whether NS fails to be κ + -saturated, i.e., are there κ + stationary subsets of κ with pairwise intersections nonstationary? Our first observation is: Theorem. NS is κ + -saturated iff for every normal ideal J on κ there is a stationary set $A \subseteq \kappa$ such that $J = NS \mid A = \{X \subseteq (...)
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  14.  15
    The Transcendental Ideality of Sets and Objects.D. L. C. Maclachlan - 1989 - Proceedings of the Sixth International Kant Congress 2 (1):251-258.
  15.  27
    Compact set valued flows: Applications in biological modelling.Jacques Demongeot, Paul Kulesal & James Muffay - 1996 - Acta Biotheoretica 44 (3-4):349-358.
    Compact set valued iterations generalize classical point iterations quite naturally by replacing the function f with a tube f in the discrete iterations equation. In Section 3, some bifurcation results about logistic tube iterations are given. In Section 4, an analogous dynamical behaviour for the phase response tube involved in the entrainment of the respiratory rhythm is studied.
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  16. Ideals of nowhere Ramsey sets are isomorphic.Szymon Plewik - 1994 - Journal of Symbolic Logic 59 (2):662-667.
    We introduce a notion of ideal type such that any two ideals with the same ideal type are isomorphic. From this we infer, under the axiom t = h, that each ideal which consists of all nowhere Ramsey sets contained in some family of infinite subsets of natural numbers is isomorphic with the ideal of all nowhere Ramsey sets.
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  17.  83
    The idealization of contingency in traditional japanese aesthetics.Robert Wicks - 2005 - Journal of Aesthetic Education 39 (3):88-101.
    In lieu of an abstract, here is a brief excerpt of the content:The Idealization of Contingency in Traditional Japanese AestheticsRobert Wicks (bio)In many popular writings that date from the initial decades of the twentieth century, and also in recent scholarly studies, "Japanese aesthetics"—insofar as we can speak sweepingly of a complicated, multidimensional, and dynamic historical phenomenon—is characterized with a set of adjectives whose present linguistic entrenchment is clearly evident. Specifically we read that traditional Japanese aesthetics is an aesthetics of imperfection, (...)
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  18.  78
    Commodious axiomatization of quantifiers in multiple-valued logic.Reiner Hähnle - 1998 - Studia Logica 61 (1):101-121.
    We provide tools for a concise axiomatization of a broad class of quantifiers in many-valued logic, so-called distribution quantifiers. Although sound and complete axiomatizations for such quantifiers exist, their size renders them virtually useless for practical purposes. We show that for quantifiers based on finite distributive lattices compact axiomatizations can be obtained schematically. This is achieved by providing a link between skolemized signed formulas and filters/ideals in Boolean set lattices. Then lattice theoretic tools such as Birkhoff's representation theorem (...)
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  19.  27
    Borel ideals vs. Borel sets of countable relations and trees.Samy Zafrany - 1989 - Annals of Pure and Applied Logic 43 (2):161-195.
  20.  35
    On Ideals of Sets and the Power Set Operation.Thomas Jech, Karel Prikry, F. Galvin, T. Jech & M. Magidor - 1985 - Journal of Symbolic Logic 50 (1):239-240.
  21.  23
    (1 other version)Ideals of Generalized Finite Sets in Lattices of α‐Recursively Enumerable Sets.Manuel Lerman - 1976 - Mathematical Logic Quarterly 22 (1):347-352.
  22.  2
    Different covering numbers of compact tree ideals.Jelle Mathis Kuiper & Otmar Spinas - forthcoming - Archive for Mathematical Logic:1-20.
    We investigate the covering numbers of some ideals on $${^{\omega }}{2}{}$$ ω 2 associated with tree forcings. We prove that the covering of the Sacks ideal remains small in the Silver and uniform Sacks model, respectively, and that the coverings of the uniform Sacks ideal and the Mycielski ideal, $${\mathfrak {C}_{2}}$$ C 2, remain small in the Sacks model.
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  23.  12
    Adding a Nonreflecting Weakly Compact Set.Brent Cody - 2019 - Notre Dame Journal of Formal Logic 60 (3):503-521.
    For n<ω, we say that theΠn1-reflection principle holds at κ and write Refln if and only if κ is a Πn1-indescribable cardinal and every Πn1-indescribable subset of κ has a Πn1-indescribable proper initial segment. The Πn1-reflection principle Refln generalizes a certain stationary reflection principle and implies that κ is Πn1-indescribable of order ω. We define a forcing which shows that the converse of this implication can be false in the case n=1; that is, we show that κ being Π11-indescribable of (...)
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  24.  96
    Jazz After Jazz : Ken Burns and the Construction of Jazz History.Theodore Gracyk - 2002 - Philosophy and Literature 26 (1):173-187.
    In lieu of an abstract, here is a brief excerpt of the content:Philosophy and Literature 26.1 (2002) 173-187 [Access article in PDF] Symposium: On Ken Burns's "Jazz" Jazz After Jazz: Ken Burns and the Construction of Jazz History Theodore Gracyk As all action is by its nature to be figured as extended in breadth and in depth, as well as in length; and so spreads abroad on all hands... so all narrative is, by its nature, of only one dimension; only (...)
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  25.  11
    The ideal of orderable subsets of a set.John L. Hickman - 1978 - Notre Dame Journal of Formal Logic 19 (4):593-598.
  26.  32
    Representations of MV-algebras by sheaves.Anna R. Ferraioli & Ada Lettieri - 2011 - Mathematical Logic Quarterly 57 (1):27-43.
    In this paper, inspired by methods of Bigard, Keimel, and Wolfenstein , we develop an approach to sheaf representations of MV-algebras which combines two techniques for the representation of MV-algebras devised by Filipoiu and Georgescu and by Dubuc and Poveda . Following Davey approach , we use a subdirect representation of MV-algebras that is based on local MV-algebras. This allowed us to obtain: a representation of any MV-algebras as MV-algebra of all global sections of a sheaf of local MV-algebras on (...)
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  27.  23
    Games with filters I.Matthew Foreman, Menachem Magidor & Martin Zeman - 2023 - Journal of Mathematical Logic 24 (3).
    This paper has two parts. The first is concerned with a variant of a family of games introduced by Holy and Schlicht, that we call Welch games. Player II having a winning strategy in the Welch game of length [Formula: see text] on [Formula: see text] is equivalent to weak compactness. Winning the game of length [Formula: see text] is equivalent to [Formula: see text] being measurable. We show that for games of intermediate length [Formula: see text], II winning implies (...)
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  28. Games with filters I.Matthew Foreman, Menachem Magidor & Martin Zeman - 2023 - Journal of Mathematical Logic 24 (3).
    Journal of Mathematical Logic, Volume 24, Issue 03, December 2024. This paper has two parts. The first is concerned with a variant of a family of games introduced by Holy and Schlicht, that we call Welch games. Player II having a winning strategy in the Welch game of length [math] on [math] is equivalent to weak compactness. Winning the game of length [math] is equivalent to [math] being measurable. We show that for games of intermediate length [math], II winning implies (...)
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  29. Notions of compactness for special subsets of ℝ I and some weak forms of the axiom of choice.Marianne Morillon - 2010 - Journal of Symbolic Logic 75 (1):255-268.
    We work in set-theory without choice ZF. A set is Countable if it is finite or equipotent with ${\Bbb N}$ . Given a closed subset F of [0, 1] I which is a bounded subset of $\ell ^{1}(I)$ (resp. such that $F\subseteq c_{0}(I)$ ), we show that the countable axiom of choice for finite sets, (resp. the countable axiom of choice AC N ) implies that F is compact. This enhances previous results where AC N (resp. the axiom (...)
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  30.  65
    The Ideal of a Rational Morality: Philosophical Compositions.Marcus George Singer - 2002 - Oxford, GB: Oxford University Press UK.
    The Ideal of a Rational Morality collects the most important essays by the distinguished moral philosopher Marcus G. Singer. Its guiding theme is the concept of a morality based in reason, which is presupposed in ordinary moral contexts and provides an ideal for improving ordinary morality and correcting moral judgements. Singer makes compelling claims that certain fundamental presuppositions are inescapable in moral thought, that fundamental moral principles can be proved, and that the concepts of truth and 'common sense' are essential (...)
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  31.  67
    Powers of the ideal of lebesgue measure zero sets.Maxim R. Burke - 1991 - Journal of Symbolic Logic 56 (1):103-107.
    We investigate the cofinality of the partial order N κ of functions from a regular cardinal κ into the ideal N of Lebesgue measure zero subsets of R. We show that when add(N) = κ and the covering lemma holds with respect to an inner model of GCH, then cf(N κ ) = max {cf(κ κ ), cf([ cf(N)] κ )}. We also give an example to show that the covering assumption cannot be removed.
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  32. The Ideals of Law: Judging and the Constitution.Jana Mohr Lone - 1996 - Dissertation, University of Washington
    The United States Constitution embodies both the real and the ideal. It is a concrete written text that uses particular words, has a history, and possesses certain limits; it is also a statement of the aspirations and dreams of a society. This dual identity requires that the Constitution be understood both as written positive law, and as an expression of a national vision and set of ideals. ;I argue for a conceptual theory of law that is positivistic in the (...)
     
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  33.  4
    The Shape of Compact Covers.Ziqin Feng & Paul Gartside - forthcoming - Journal of Symbolic Logic:1-15.
    For a space X let $\mathcal {K}(X)$ be the set of compact subsets of X ordered by inclusion. A map $\phi :\mathcal {K}(X) \to \mathcal {K}(Y)$ is a relative Tukey quotient if it carries compact covers to compact covers. When there is such a Tukey quotient write $(X,\mathcal {K}(X)) \ge _T (Y,\mathcal {K}(Y))$, and write $(X,\mathcal {K}(X)) =_T (Y,\mathcal {K}(Y))$ if $(X,\mathcal {K}(X)) \ge _T (Y,\mathcal {K}(Y))$ and vice versa. We investigate the initial structure of pairs $(X,\mathcal (...)
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  34. Decreasing chains of algebraic sets.Harvey Friedman - manuscript
    An ideal in a commutative ring R with unit is a nonempty I Õ R such that for all x,y Œ I, z Œ R, we have x+y and xz Œ I. A set of generators for I is a subset of I such that I is the least ideal containing that subset.
     
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  35. The ideal of harmony in ancient chinese and greek philosophy.Chenyang Li - 2008 - Dao: A Journal of Comparative Philosophy 7 (1):81-98.
    This article offers a study of the early formation and development of the ideal of harmony in ancient Chinese philosophy and ancient Greek philosophy. It shows that, unlike the Pythagorean notion of harmony, which is primarily based on a linear progressive model with a pre-set order, the ancient Chinese concept of harmony is best understood as a comprehensive process of harmonization. It encompasses spatial as well as temporal dimensions, metaphysical as well as moral and aesthetical dimensions. It is a fundamentally (...)
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  36. On ideals of subsets of the plane and on Cohen reals.Jacek Cichoń & Janusz Pawlikowski - 1986 - Journal of Symbolic Logic 51 (3):560-569.
    Let J be any proper ideal of subsets of the real line R which contains all finite subsets of R. We define an ideal J * ∣B as follows: X ∈ J * ∣B if there exists a Borel set $B \subset R \times R$ such that $X \subset B$ and for any x ∈ R we have $\{y \in R: \langle x,y\rangle \in B\} \in \mathscr{J}$ . We show that there exists a family $\mathscr{A} \subset \mathscr{J}^\ast\mid\mathscr{B}$ of power ω (...)
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  37.  99
    A Tale of Two Sets: Public Reason in Equilibrium.Gerald Gaus - 2011 - Public Affairs Quarterly 25 (4):305-25.
    Public reason liberalism is a family of theories according to which liberal political institutions, social structures, and/or basic social rules are politically or morally justified if and only if they can be endorsed from the perspective of each and every free and equal "reasonable and rational" person. Let us call these persons "the members of the justificatory public." Public reason liberalism idealizes the members of the justificatory public in three senses. First, the members of the justificatory public are assumed to (...)
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  38.  90
    Carnap's ideal of explication and naturalism.Pierre Wagner (ed.) - 2012 - New York, NY: Palgrave-Macmillan.
    Carnap's ideal of explication has become a key concept in analytic philosophy and the basis of a method of analysis which may be considered as an alternative to various forms of naturalism, including Quine's conception of a naturalized epistemology. More recently, new light has been shed on this aspect of the classical Carnap-Quine debate by contemporary philosophers. Whereas Michael Friedman articulated a notion of relativized a priori which owes much to Carnap's internal/external distinction, André Carus attempted to restate Carnap's ideal (...)
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  39.  39
    Why Sparing the Rod Does Not Spoil the Child: A Critique of the “Strict Father” Model in Transnational Governance.Patrick Haack & Andreas Georg Scherer - 2014 - Journal of Business Ethics 122 (2):225-240.
    The United Nations Global Compact is one of the largest transnational governance schemes. Its success or failure, however, is a matter of debate. Drawing on research in cognitive linguistics, we argue that when evaluators discuss the UNGC, they apply the metaphorical concept of the family: the UNGC corresponds to the “family,” the UNGC headquarter to the “parent” and the business participants of the UNGC to the “children” of the family. As a corollary, evaluators’ implicit understanding of how a family (...)
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  40. Compact cylindric set algebras.György Serény - 1985 - Bulletin of the Section of Logic 14 (2):57-63.
    N´emeti remarked that the notion of compactness of cylindric of algebras corresponds to the notion of universality of models in logic [5]. The purpose of this paper is to formulate this correspondence in a purely algebraic setting.
     
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  41.  11
    On exceeding determination and the ideal of reason: Immanuel Kant, William Desmond and the noumenological principle.Christopher David Shaw - 2012 - Newcastle upon Tyne: Cambridge Scholars Press.
    On Exceeding Determination and the Ideal of Reason: Immanuel Kant, William Desmond, and the Noumenological Principle examines the critical philosophy of Immanuel Kant, as it bears on theological principles. Focusing on the foundational ideas (of self, world, and God) that constitute Kant's metaphysical system, Shaw argues that these ideal projections of the rational structures of the thinking subject only conceal and obfuscate the more robust sense of the real that exists behind all phenomenal appearances. This book aims to critically assess (...)
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  42.  39
    Two notions of compactness in Gödel logics.Petr Cintula - 2005 - Studia Logica 81 (1):99-123.
    Compactness is an important property of classical propositional logic. It can be defined in two equivalent ways. The first one states that simultaneous satisfiability of an infinite set of formulae is equivalent to the satisfiability of all its finite subsets. The second one states that if a set of formulae entails a formula, then there is a finite subset entailing this formula as well. In propositional many-valued logic, we have different degrees of satisfiability and different possible definitions of entailment, hence (...)
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  43.  25
    The existence of free ultrafilters on ω does not imply the extension of filters on ω to ultrafilters.Eric J. Hall, Kyriakos Keremedis & Eleftherios Tachtsis - 2013 - Mathematical Logic Quarterly 59 (4-5):258-267.
    Let X be an infinite set and let and denote the propositions “every filter on X can be extended to an ultrafilter” and “X has a free ultrafilter”, respectively. We denote by the Stone space of the Boolean algebra of all subsets of X. We show: For every well‐ordered cardinal number ℵ, (ℵ) iff (2ℵ). iff “ is a continuous image of ” iff “ has a free open ultrafilter ” iff “every countably infinite subset of has a limit point”. (...)
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  44.  36
    On partitions of the real line into compact sets.Ludomir Newelski - 1987 - Journal of Symbolic Logic 52 (2):353-359.
  45.  32
    Algebraic Models of Sets and Classes in Categories of Ideals.Steve Awodey, Henrik Forssell & Michael A. Warren - unknown
    We introduce a new sheaf-theoretic construction called the ideal completion of a category and investigate its logical properties. We show that it satisfies the axioms for a category of classes in the sense of Joyal and Moerdijk [17], so that the tools of algebraic set theory can be applied to produce models of various elementary set theories. These results are then used to prove the conservativity of different set theories over various classical and constructive type theories.
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  46.  48
    Ideal Objects for Set Theory.Santiago Jockwich, Sourav Tarafder & Giorgio Venturi - 2022 - Journal of Philosophical Logic 51 (3):583-602.
    In this paper, we argue for an instrumental form of existence, inspired by Hilbert’s method of ideal elements. As a case study, we consider the existence of contradictory objects in models of non-classical set theories. Based on this discussion, we argue for a very liberal notion of existence in mathematics.
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  47.  13
    Photographing Yosemite Digital Field Guide.Lewis Kemper - 2010 - Wiley.
    The ideal companion guide for capturing awe-inspiring photos of Yosemite! Whether using a compact camera or a high-end dSLR, this companion guide provides you with detailed information for taking spectacular shots of some of the most recognizable landmarks in the world. Whether you aim to capture memorable photos of Half Dome, El Capitan, Vernal Fall, Mariposa Grove, or one of Yosemite's other many remarkable attractions, this portable resource goes where you go and walks you through valuable tips and techniques (...)
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  48.  6
    Photographing San Francisco Digital Field Guide.Bruce Sawle - 2010 - Wiley.
    A compact, full-color companion guide to photographing San Francisco! Whether using a full-featured compact camera or a high-end dSLR, this companion guide provides you with detailed information for taking stunning shots of beautiful San Francisco. Whether you aim to capture breathtaking photos of the majestic Golden Gate Bridge, crooked Lombard Street, infamous Alcatraz, or unique Victorian homes, this portable resource goes where you go and walks you through valuable tips and techniques for taking the best shot possible. You'll (...)
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  49. Deference and Ideals of Practical Agency.Jonathan Knutzen - 2021 - Canadian Journal of Philosophy 51 (1):17-32.
    This paper develops a moderate pessimist account of moral deference. I argue that while some pessimist explanations of the puzzle of moral deference have been misguided in matters of detail, they nevertheless share an important insight, namely that there is a justified moral agency ideal grounded in pro tanto reasons against moral deference. This thought is unpacked in terms of a set of values associated with the practice of morality. I conclude by suggesting that the solution to the puzzle of (...)
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  50.  48
    The Lattice of Kernel Ideals of a Balanced Pseudocomplemented Ockham Algebra.Jie Fang, Lei-Bo Wang & Ting Yang - 2014 - Studia Logica 102 (1):29-39.
    In this note we shall show that if L is a balanced pseudocomplemented Ockham algebra then the set ${\fancyscript{I}_{k}(L)}$ of kernel ideals of L is a Heyting lattice that is isomorphic to the lattice of congruences on B(L) where ${B(L) = \{x^* | x \in L\}}$ . In particular, we show that ${\fancyscript{I}_{k}(L)}$ is boolean if and only if B(L) is finite, if and only if every kernel ideal of L is principal.
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