This volume is based on the talks given at the Workshop on Infinity and Truth held at the Institute for Mathematical Sciences, National University of Singapore, from 25 to 29 July 2011. The chapters are by leading experts in mathematical and philosophical logic that examine various aspects of the foundations of mathematics. The theme of the volume focuses on two basic foundational questions: (i) What is the nature of mathematical truth and how does one resolve questions that are formally unsolvable (...) within the Zermelo Fraenkel Set Theory with the Axiom of Choice, and (ii) Do the discoveries in mathematics provide evidence favoring one philosophical view over others? These issues are discussed from the vantage point of recent progresses in foundational studies. The final chapter features questions proposed by the participants of the Workshop that will drive foundational research. The wide range of topics covered here will be of benefit to students, researchers and mathematicians interested in the foundations of mathematics. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:uippraisals from the 'Past THE CLEAREST INTELLECT OF OUR AGEl H UGH MACLENNAN 19°7-199° R cently I have been rereading Bertrand Russell, and in so doing I suddenly realized that lowe to this man a good deal of such happiness as I enjoy. Over the years I had forgotten how great my debt was, but when I reread one of his books which I first read as a student, (...) I understood the extent to which he had liberated me from the psychological sadism of Calvin and Knox, to whom I had been unduly exposed when young. It is probably impossible for anyone entirely to escape once these two have got their hands around his throat, but Russell enabled me to escape a litde. 1 [This essay was recently discovered during the cataloguing for BRACERS of an obscure class of correspondence. Mr. Joseph w. Devine had sent Russell a clipping of the essay's appearance in' the Philadelphia Sunday But/etin, of 15 July 1962. I had long thought, from reading Elspeth Cameron's Hugh MacLennan: a Writers Life (1981), that he showed signs not only of having been influenced by Russell but of being the sOrt of person who is attracted to Russell's way of thinking. A promising tide in the same scholar's bibliography ofMacLennan turned out to be a fuller version of the clipping. "The Clearest Intellect of Our Age" is reprinted from The Montreal Star, 14 July 1962, "Entertainments" sec., p. 5. Russell did influence MacLennan. Neither the Russell Archives nor the inventory of the Maclennan papers at the Universiry of Calgary reveals personal contact berween the rwo. I wish I had asked MacLennan about contacts and influence seventeen years ago, when I sent him an early issue of Russell He commented: ''1 found your journal fascinating and never before had read that beautiful thing Russell wrote in his early days with Whitehead:" He is referring to the essay on the status of women in No.6, now in Papers 12.-Ed.] russell: the Journal ofthe Benrand Russell Archives McMaster Unive..ity Libraty Press noS. 11 (summer 1991): 83-5 ISSN 00,6-01631 84 HUGH MACLENNAN I suppose he really is the greatest man alive, in the sense that his teaching grows and his teaching is good, but it is pointless to argue the point between him and Churchill. It is wonderful, however, that many think he is our greatest man and that he has become an international hero to millions of the thoughtful youth. He must be the first pure logician who ever was that. Until he took his stand against nuclear war, he never appealed to the passions. He lacked the aggressions which youth admires. He never said: "Come live with me and I will be your master"; or, "Follow me and I will purge you of your sins." He had no use for self-sacrifice as such. He simply said, in effect: "Happiness is good. If you desire it, you must be reasonable." As he was intelligent enough to know that anyone who teaches that happiness is good, and teaches how to achieve it, is sute to be considered subversive to a Christian-commercial society, he bore no personal resentment when society persecuted him. The young know, of course, that Russell is now assumed by the experts to be the most important philosopher since Hume, but that is not why they love him. They love him for the sublime civilization of his courage, for his refusal to let an intensely kind nature blunt his respect for truth. They love him because he loves life even in the twentieth century; and they love him most of all because he is engage. And of course they also love the wit which refuses to be made tongue-tied by those who insist that whenever one speaks of sex or religion one must be solemn. Russell's wit is worth the study of any writer. It is based on mathematics, and Russell would agree, I think, with the remark Camillien Houde once made to me when I asked the famous mayor of Montreal how he was always able to make people laugh. Houde replied... (shrink)

Asperó and Schindler have completely solved the Axiom [Formula: see text] vs. [Formula: see text] problem. They have proved that if [Formula: see text] holds then Axiom [Formula: see text] holds, with no additional assumptions. The key question now concerns the relationship between [Formula: see text] and Axiom [Formula: see text]. This is because the foundational issues raised by the problem of Axiom [Formula: see text] vs. [Formula: see text] arguably persist in the problem of Axiom [Formula: see text] vs. (...) [Formula: see text]. The first of our two main theorems is that Axiom [Formula: see text] is equivalent to Axiom [Formula: see text], and as a corollary we show that Axiom [Formula: see text] fails in all the known models of [Formula: see text]. This suggests that [Formula: see text] actually refutes Axiom [Formula: see text]. Our second main theorem is that the [Formula: see text] Conjecture holds assuming [Formula: see text]. This is the strongest partial result known on this conjecture which is one of the central open problems of [Formula: see text]-theory and [Formula: see text]-logic. These results identify a fundamental asymmetry between the Continuum Hypothesis and any axiom which is both [Formula: see text]-expressible and which implies [Formula: see text], on the basis of generic absoluteness for the simplest of the nontrivial sentences of Third-Order Number Theory. These are the [Formula: see text]-sentences with no parameters. Such sentences are those which simply assert the existence of a set [Formula: see text] for which some property involving only quantification over [Formula: see text] holds. (shrink)

We give a fairly complete account which first shows that the solution to the inner model problem for one supercompact cardinal will yield an ultimate version ofLand then shows that the various current approaches to inner model theory must be fundamentally altered to provide that solution.

We investigate both iteration hypotheses and extender models at the level of one supercompact cardinal. The HOD Conjecture is introduced and shown to be a key conjecture both for the Inner Model Program and for understanding the limits of the large cardinal hierarchy. We show that if the HOD Conjecture is true then this provides strong evidence for the existence of an ultimate version of Gödel's constructible universe L. Whether or not this "ultimate" L exists is now arguably the central (...) issue for the Inner Model Program. (shrink)

We investigate large cardinal axioms beyond the level of ω-huge in context of the universality of the suitable extender models of [Suitable Extender Models I, J. Math. Log.10 101–339]. We show that there is an analog of ADℝ at the level of ω-huge, more precisely the construction of the minimum model of ADℝ generalizes to the level of Vλ+1. This allows us to formulate the indicated generalization of ADℝ and then to prove that if the axiom holds in V at (...) a proper class of λ then in every suitable extender model, the axiom holds at a proper class of λ. (shrink)

The results of this paper concern the effective cardinal structure of the subsets of [ω1]<ω1, the set of all countable subsets of ω1. The main results include dichotomy theorems and theorems which show that the effective cardinal structure is complicated.

We prove that if $V = L [s]$ where $s$ is an $\omega$ -sequence of ordinals then the GCH holds.

The main theorem is that the Ultrafilter Axiom of Woodin :115–37, 2011) must fail at all cardinals where the Axiom I0 holds, in all non-strategic extender models subject only to fairly general requirements on the non-strategic extender model.

One of the most distinctive and intriguing developments of modern set theory has been the realization that, despite widely divergent incentives for strengthening the standard axioms, there is essentially only one way of ascending the higher reaches of infinity. To the mathematical realist the unexpected convergence suggests that all these axiomatic extensions describe different aspects of the same underlying reality.

We prove that every countable relation on the enumeration degrees, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} ${\frak E}$\end{document}, is uniformly definable from parameters in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} ${\frak E}$\end{document}. Consequently, the first order theory of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} ${\frak E}$\end{document} is recursively isomorphic to the second order theory of arithmetic. By an effective version of coding lemma, we show that the first order (...) theory of the enumeration degrees of the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $\Sigma^0_2$\end{document} sets is not decidable. (shrink)

The Necessary Maximality Principle for c. c. c. forcing with real parameters is equiconsistent with the existence of a weakly compact cardinal. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim).

We consider the possible complexity of the set of reals belonging to an inner model M of set theory. We show that if this set is analytic then either 1M is countable or else all reals are in M. We also show that if an inner model contains a superperfect set of reals as a subset then it contains all reals. On the other hand, it is possible to have an inner model M whose reals are an uncountable Fσ set (...) and which does not have all reals. A similar construction shows that there can be an inner model M which computes correctly 1, contains a perfect set of reals as a subset and yet not all reals are in M. These results were motivated by questions of H. Friedman and K. Prikry. (shrink)

In 1985 the second author showed that if there is a proper class of measurable Woodin cardinals and $V^{B1} $ and $V^{B2} $ are generic extensions of V satisfying CH then $V^{B1} $ and $V^{B2} $ agree on all $\Sigma _1^2 $ -statements. In terms of the strong logic Ω-logic this can be reformulated by saying that under the above large cardinal assumption ZFC + CH is Ω-complete for $\Sigma _1^2 $ Moreover. CH is the unique $\Sigma _1^2 $ -statement (...) with this feature in the sense that any other $\Sigma _1^2 $ -statement with this feature is Ω-equivalent to CH over ZFC. It is natural to look for other strengthenings of ZFC that have an even greater degree of Ω-completeness. For example, one can ask for recursively enumerable axioms A such that relative to large cardinal axioms ZFC + A is Ω-complete for all of third-order arithmetic. Going further, for each specifiable segment $V_\lambda $ of the universe of sets (for example, one might take $V_\lambda $ to be the least level that satisfies there is a proper class of huge cardinals), one can ask for recursively enumerable axioms A such that relative to large cardinal axioms ZFC + A is Ω-complete for the theory of $V_\lambda $ . If such theories exist, extend one another, and are unique in the sense that any other such theory B with the same level of Ω-completeness as A is actually Ω-equivalent to A over ZFC, then this would show that there is a unique Ω-complete picture of the successive fragments of the universe of sets and it would make for a very strong case for axioms complementing large cardinal axioms. In this paper we show that uniqueness must fail. In particular, we show that if there is one such theory that Ω-implies CH then there is another that Ω-implies¬CH. (shrink)

We extend work of H. Friedman, L. Harrington and P. Welch to the third level of the projective hierarchy. Our main theorems say that (under appropriate background assumptions) the possibility to select definable elements of non-empty sets of reals at the third level of the projective hierarchy is equivalent to the disjunction of determinacy of games at the second level of the projective hierarchy and the existence of a core model (corresponding to this fragment of determinacy) which must then contain (...) all real numbers. The proofs use Sacks forcing with perfect trees and core model techniques. (shrink)

J. Łoś raised the following question: Under what conditions can a countable partially ordered set be extended to a dense linear order merely by adding instances of comparability ? We show that having such an extension is a Σ 1 l -complete property and so there is no Borel answer to Łoś's question. Additionally, we show that there is a natural Π 1 l -norm on the partial orders which cannot be so extended and calculate some natural ranks in that (...) norm. (shrink)

The HOD Dichotomy Theorem states that if there is an extendible cardinal, δ, then either HOD is “close” to V or HOD is “far” from V. The question is whether the future will lead to the first or the second side of the dichotomy. Is HOD “close” to V, or “far” from V? There is a program aimed at establishing the first alternative—the “close” side of the HOD Dichotomy. This is the program of inner model theory. In recent years the (...) third author has provided evidence that there is an ultimate inner model—Ultimate-L—and he has isolated a natural conjecture associated with the model—the Ultimate-L Conjecture. This conjecture implies that that the first alternative holds—HOD is “close” to V. This is the future in which pattern prevails. In this paper we introduce a very different program, one aimed at establishing the second alternative—the “far” side of the HOD Dichotomy. This is the program of large cardinals beyond choice. Kunen famously showed that if AC holds then there cannot be a Reinhardt cardinal. It has remained open whether Reinhardt cardinals are consistent in ZF alone. It turns out that there is an entire hierarchy of choiceless large cardinals of which Reinhardt cardinals are only the beginning, and, surprisingly, this hierarchy appears to be highly ordered and amenable to systematic investigation, as we shall show in this paper. The point is that if these choiceless large cardinals are consistent then the Ultimate-L Conjecture must fail. This is the future where chaos prevails. (shrink)

We prove the following result which is due to the third author. Let [Formula: see text]. If [Formula: see text] determinacy and [Formula: see text] determinacy both hold true and there is no [Formula: see text]-definable [Formula: see text]-sequence of pairwise distinct reals, then [Formula: see text] exists and is [Formula: see text]-iterable. The proof yields that [Formula: see text] determinacy implies that [Formula: see text] exists and is [Formula: see text]-iterable for all reals [Formula: see text]. A consequence is (...) the Determinacy Transfer Theorem for arbitrary [Formula: see text], namely the statement that [Formula: see text] determinacy implies [Formula: see text] determinacy. (shrink)

We prove the following result which is due to the third author. Let [Formula: see text]. If [Formula: see text] determinacy and [Formula: see text] determinacy both hold true and there is no [Formula: see text]-definable [Formula: see text]-sequence of pairwise distinct reals, then [Formula: see text] exists and is [Formula: see text]-iterable. The proof yields that [Formula: see text] determinacy implies that [Formula: see text] exists and is [Formula: see text]-iterable for all reals [Formula: see text]. A consequence is (...) the Determinacy Transfer Theorem for arbitrary [Formula: see text], namely the statement that [Formula: see text] determinacy implies [Formula: see text] determinacy. (shrink)

'The infinite! No other question has ever moved so profoundly the spirit of man; no other idea has so fruitfully stimulated his intellect; yet no other concept stands in greater need of clarification than that of the infinite.' David Hilbert (1862-1943). This interdisciplinary study of infinity explores the concept through the prism of mathematics and then offers more expansive investigations in areas beyond mathematical boundaries to reflect the broader, deeper implications of infinity for human intellectual thought. More than a dozen (...) world-renowned researchers in the fields of mathematics, physics, cosmology, philosophy, and theology offer a rich intellectual exchange among various current viewpoints, rather than a static picture of accepted views on infinity. The book starts with a historical examination of the transformation of infinity from a philosophical and theological study to one dominated by mathematics. It then offers technical discussions on the understanding of mathematical infinity. Following this, the book considers the perspectives of physics and cosmology: Can infinity be found in the real universe? Finally, the book returns to questions of philosophical and theological aspects of infinity"--Provided by publisher. (shrink)

A personal journey in and through comparison -- To what can I compare thee -- History -- Possibilities -- Context -- Future.

Employees perceive illegitimate tasks as inappropriate assignments because such tasks are beyond what they expect to do in any given job position. Extant literature indicates that, in addition to creating psychological strain and reducing well-being, illegitimate task assignments can result in counterproductive work behavior. This study extends the literature by examining whether illegitimate tasks may lead to two specific forms of CWB targeting organizations: destructive voice and time theft. To understand how and when this happens, we investigate the mediating role (...) of moral disengagement and the moderating role of psychological entitlement. Survey results based on 258 supervisor–subordinate dyads in China reveal that illegitimate tasks are positively related to destructive voice and time theft through moral disengagement. Furthermore, psychological entitlement strengthens the positive relationship between illegitimate tasks and moral disengagement and the indirect effect of illegitimate tasks on destructive voice and time theft. Overall, the findings provide insightful theoretical and managerial implications for research related to illegitimate tasks and CWB. (shrink)

Lenn E. Goodman is professor of philosophy and as the Andrew W. Mellon professor in the humanities at Vanderbilt University in Nashville, Tennessee. Trained in medieval Arabic and Hebrew philosophy and intellectual history, his prolific scholarship has covered the entire history of philosophy from antiquity to the present with a focus on medieval Jewish philosophy. A synthetic philosopher, Goodman has drawn on Jewish religious sources (e.g., Bible, Midrash, Mishnah, and Talmud) as well as philosophic sources (Jewish, Muslim, and Christian), in (...) an attempt to construct his own distinctive theory about the natural basis of morality and justice. Taking his cue from medieval Jewish philosophers such as Maimonides, Goodman offers a new theoretical framework for Jewish communal life that is attentive to contemporary philosophy and science. (shrink)

In this study, we investigated whether differences in the experience of regret may be a potential explanation for damaging behaviours associated with psychopathy and criminal offending. Participants were incarcerated offenders (n = 60) and non-incarcerated controls (n = 20). Psychopathic traits were characterised with the Psychopathic Checklist: Screening Version. Regret was assessed by responses to outcomes on a simulated gambling task. Incarcerated offenders experienced a reduced sense of regret as compared to non-incarcerated controls. We obtained some evidence that specific psychopathic (...) factors and facets could differentially relate to the experience and use of emotions. Our data provide initial evidence of important associations between negative emotions and decision behaviour in the context of criminal offending. (shrink)

Three experiments test the theory that verb meanings are more malleable than noun meanings in different semantic contexts, making a previously seen verb difficult to remember when it appears in a new semantic context. Experiment 1 revealed that changing the direct object noun in a transitive sentence reduced recognition of a previously seen verb, whereas changing the verb had little impact on noun recognition. Experiment 2 revealed that verbs exhibited context effects more similar to those shown by superordinate nouns rather (...) than basic-level nouns. Experiment 3 demonstrated that the degree of meaning change in a target word resulting from changes in semantic context influenced the magnitude of context effects, but context effects remained larger for verbs than for nouns even when the degree of meaning change was similar for nouns and verbs. These results are discussed with respect to the imageability and grammatical roles played by nouns and verbs in a sentence. (shrink)