Timothy Williamson gives an original and provocative treatment of deep metaphysical questions about existence, contingency, and change, using the latest resources of quantified modal logic. Contrary to the widespread assumption that logic and metaphysics are disjoint, he argues that modal logic provides a structural core for metaphysics.

Colburn (computer science, U. of Minnesota-Duluth) has a doctorate in philosophy and an advanced degree in computer science; he's worked as a philosophy professor, a computer programmer, and a research scientist in artificial intelligence. Here he discusses the philosophical foundations of artificial intelligence; the new encounter of science and philosophy (logic, models of the mind and of reasoning, epistemology); and the philosophy of computer science (touching on math, abstraction, software, and ontology).

In this paper, I intend to demonstrate that in the Monologion Saint Anselm affirms the priority of the via negativa over the via positiva.More precisely, I shall argue that in that text Anselm defends a distinctive thesis with three components. There is, to begin with,a semantic component, according to which, all of our words for God—including those purporting to tell us what God is—fall utterlyshort of their mark. A consequence of this is that none of our speech is capable of (...) describing the reality that is God. There is, inaddition, an epistemic component according to which there is no way for us to understand what God is; we can only know what Godis not. In consequence, we have no way of directly grasping God or of comprehending God’s being. Finally there is a metaphysicalcomponent according to which what God is in himself is an infinite and ineffable mystery. A consequence of this would be that Godturns out to have nothing at all in common with his creatures. (shrink)

The philosophical relevance of experimental psychology is hard to dispute. Much more controversial is the so‐called negative program's critique of armchair philosophical methodology, in particular the reliance on ‘intuitions’ about thought experiments. This chapter responds to that critique. It argues that, since the negative program has been forced to extend the category of intuition to ordinary judgments about real‐life cases, the critique is in immediate danger of generating into global scepticism, because all human judgments turn out to depend on intuitions. (...) Recently, some proponents of the negative program have tried to demarcate the target of their critique more narrowly. However, their attempts are still far too indiscriminate, and over‐generate scepticism. Nevertheless, once experimental philosophy has refined its own methodology, it may contribute to the refinement of the methodology of mainstream philosophy, by filtering out the effects of cognitive bias, although it offers no prospect of doing without judgments on real or imaginary cases. (shrink)

The main aim of this book is to encourage philosophers to take a more sophisticated and scientific attitude to their handling of evidence, both in theory and in practice, by introducing two categories neglected in current metaphilosophy. The first category is that of heuristics. These are typically efficient ways of solving problems of some kind, quick and easy to use, and mostly but not always reliable. Those most probably central to philosophical methodology are more or less humanly universal general cognitive (...) heuristics which we employ without conscious reflection. In many plausible cases, they can be shown to be implicitly inconsistent, and so cannot be perfectly valid, though for evolutionary reasons they are likely to be fairly reliable in normal cases. Such heuristics may well generate false but convincing data as applied to some actual or hypothetical. Arguably, the heuristics also generate philosophical paradoxes, just as heuristics embedded in our perceptual systems generate perceptual illusions. The second category is that of overfitting. This is a recognized pathology in science, when models are allowed to become very complicated to achieve a close fit with data, and further complications typically keep having to be made as new data comes in. When the data contains errors, such theorizing provides little insight. Scientists guard against overfitting by strongly preferring comparatively simple models. Philosophers should learn to do the same. This approach is applied to debates between coarse-grained (intensionalist) and fine-grained (hyperintensionalist) theories of metaphysics, ascriptions of propositional attitudes, and other topics, in favour of intensionalism. (shrink)

Timothy Williamson; VII*—Equivocation and Existence, Proceedings of the Aristotelian Society, Volume 88, Issue 1, 1 June 1988, Pages 109–128, https://doi.org/10.

The article reviews two books by Bernard Williams including "Philosophy As a Humanistic Discipline" and "The Sense of the Past.".

In this paper, we explore how free will should be understood within the Christian doctrine of the Incarnation, particularly on the assumption of traditional Christology. We focus on two issues: reconciling Christ's free will with the claim that Christ's human will was subjected to the divine will in the Incarnation; and reconciling the claims that Christ was fully human and free with the belief that Christ, since God, could not sin.

The divine architect and his temple -- The divine artisan and his images -- The divine farmer and his plantings -- The divine monarch and his regents -- The divine warrior and his army -- The divine shepherd and his flock -- The divine patron and his household.

In conversations between native speakers, words such as ‘same’ and ‘identical’ do not usually cause much difficulty. We take it for granted that others use them with the same sense as we do. If it is unclear whether numerical or qualitative identity is intended, a brief gloss such as ‘one thing not two’ for the former or ‘exactly alike’ for the latter removes the unclarity. In this paper, numerical identity is intended. A particularly conscientious and logically aware speaker might explain (...) what ‘identical’ means in her. (shrink)

What limits ought there be on a state’s ability to create a homogeneous society, to increase or perpetuate non-diversity, or to create hierarchies within existing diversity? This article examines those questions with reference to the Lieberman Plan—which proposes to transfer populated territories from Israel to the Palestine in exchange for Jewish settlements on the West Bank— as an abstract exercise in demographic transformation by the state. First the article considers if the Lieberman plan would “work”: Would it create the alterations (...) it proposes, and would those changes achieve a stable, peaceful, perhaps even just settlement? It finds that though there is debate about the range of effect, there is little doubt that transfer would alter the state’s demography. It then turns to the international standards that might govern the transfer of territory and the denaturalization of citizens, to see how they would characterize such a plan. It finds that comparisons to ethnic cleansing are inapposite, and that norms protecting citizenship are considerably more complex than they first appear—even allowing ethnically targeted denaturalization in some cases. The article then analyzes the loyalty provisions of the Lieberman Plan, and notes that, contrary to the usual normative assumption that citizenship is tied to the state, the foundations of citizenship are actually a habitual or formative link to a given territory, which in turn creates a right to citizenship not in any particular state, but in the one that incidentally is sovereign over that territory. This interaction of citizenship and territory, when considered together with norms requiring equal protection for all citizens, suggests that the polity has an interest in defining its own territorial scope, and thereby its membership. The legal regime is ambiguous, and therefore deliberations about this question are in the realm of politics. The article demonstrates how transfer’s assimilation to existing norms suggests a novel interpretation of selfdetermination with far-reaching consequences for both sides of the conflict. Finally, the article notes that international law, though it polices excesses, is largely silent on the principal determinant of demography: the fact of state control over territory. (shrink)

First published Sat Apr 5, 2003; most recent substantive revision Wed Aug 22, 2018. -/- Samuel Clarke (1675–1729) was the most influential British philosopher in the generation between Locke and Berkeley. His philosophical interests were mostly in metaphysics, theology, and ethics.

This chapter argues that one's total evidence is simply one's total knowledge. Evidence is primarily relevant to evaluating propositions of whose truth values one is ignorant. Since knowledge is not to be analysed in terms of justification, there is no circularity in using knowledge to analyse justification by evidence. Thus, the attempt to reorient epistemology towards justification rather than knowledge is a mistake. The need for evidence to be propositional is emphasized by consideration of its role in falsification, inference to (...) the best explanation, and Bayesian confirmation. (shrink)

The chapter bases a theory of evidential probability on the equation of knowledge with evidence. It is a form of objective rather than subjective Bayesianism. Updating on new evidence is structured in a way that allows propositions to lose as well as gain probability. The account is integrated with possible worlds models of epistemic logic. Since one does not always know what one knows, the accessibility relation is not an equivalence relation, which has the effect that prior probability can diverge (...) from expected posterior probability. (shrink)

Section 1 introduces the category of objective modality, closely related to linguists’ category of circumstantial or dynamic modals, and explains metaphysical modality as its maximal element. Section 2 discusses various kinds of skepticism about modality, as in Hume and recent authors, and argues that it is illmotivated to apply such skepticism to metaphysical modality but not to more restricted objective modalities, including nomic modality. Section 3 suggests that the role of counterfactual conditionals in applications of scientific theories involves an objective (...) modal dimension. Section 4 briefly discusses the role of objective probabilities in scientific theories as exemplifying the scientific study of objective modality. Section 5 summarizes a case study of dynamical systems theory, widely used in natural science, as a mathematical theory whose intended applications are objectively modal, as perspicuously articulated in a language with modal and temporal operators and propositional quantification. State spaces in natural science characterize objective possibilities. Section 6 argues that, although those possibilities are usually more restricted than metaphysical possibility, their scientific study is a partial study of metaphysical possibility too. (shrink)

It has been suggested that damage to anterior regions of the left hemisphere results in a dissociation in the perception and lexical activation of past-tense forms. Specifically, in a lexical-decision task in which past-tense primes immediately precede present-tense targets, such patients demonstrate significant priming for irregular verbs (spoke–speak), but, unlike control participants, fail to do so for regular verbs (looked–look). Here, this behavioral dissociation was first confirmed in a group of eleven patients with damage to the pars opercularis (BA 44) (...) and pars triangularis (BA 45) of the left inferior frontal gyrus (i.e., Broca's area). Two conditions containing word-onset orthographic–phonological overlap (bead–bee, barge–bar) demonstrated that the disrupted regular-verb priming was accompanied by, and covaried with, disrupted ortho-phonological priming, regardless of whether prime stimuli contained the regular inflectional rhyme pattern. Further, the dissociation between impaired regular-verb and preserved irregular-verb priming was shown to be continuous rather than categorical; priming for weak-irregular verbs (spent–spend) was intermediate in size between that of regular verbs and strong verbs. Such continuous dissociations grounded in ortho-phonological relationships between present- and past-tense forms are predicted by single-system, connectionist approaches to inflectional morphology and not predicted by current dual-system, rule-based models. Event-related potential data demonstrated that N400 priming effects were intact for both regular and irregular verbs, suggesting that the absence of significant regular-verb priming in the response time data did not result from a disruption of lexical access, and may have stemmed instead from post-lexical events such as covert articulation, segmentation strategies, and/or cognitive control. (shrink)

Call a set A n-correctable if every set Turing reducible to A via a Turing machine that on any input makes at most n queries is Turing reducible to A via a Turing machine that on any input makes at most n-queries and on any input halts no matter what answers are given to its queries. We show that if a c.e. set A is n-correctable for some n ≥ 2, then it is n-correctable for all n. We show that (...) this is the optimal such result by constructing a c.e. set that is 1-correctable but not 2-correctable. The former result is obtained by examining the logical closure properties of c.e. sets that are 2-correctable. (shrink)