I develop a non-representationalist account of mathematical thought, on which the point of mathematical theorizing is to provide us with the conceptual capacity to structure and articulate information about the physical world in an epistemically useful way. On my view, accepting a mathematical theory is not a matter of having a belief about some subject matter; it is rather a matter of structuring logical space, in a sense to be made precise. This provides an elegant account of the (...) cognitive utility of mathematics. Further, it makes explicit how the brand of non-representationalism I develop is compatible with there being substantive rationality constraints on our mathematical theorizing. (shrink)

Can we design a perfect democratic decision procedure? Condorcet famously observed that majority rule, our paradigmatic democratic procedure, has some desirable properties, but sometimes produces inconsistent outcomes. Revisiting Condorcet’s insights in light of recent work on the aggregation of judgments, I show that there is a conflict between three initially plausible requirements of democracy: “robustness to pluralism”, “basic majoritarianism”, and “collective rationality”. For all but the simplest collective decision problems, no decision procedure meets these three requirements at once; at most (...) two can be met together. This “democratic trilemma” raises the question of which requirement to give up. Since different answers correspond to different views about what matters most in a democracy, the trilemma suggests a map of the “logical space” in which different conceptions of democracy are located. It also sharpens our thinking about other impossibility problems of social choice and how to avoid them, by capturing a core structure many of these problems have in common. More broadly, it raises the idea of “cartography of logical space” in relation to contested political concepts. (shrink)

Our conception of logical space is the set of distinctions we use to navigate the world. Agustn Rayo argues that this is shaped by acceptance or rejection of 'just is'-statements: e.g. 'to be composed of water just is to be composed of H2O'. He offers a novel conception of metaphysical possibility, and a new trivialist philosophy of mathematics.

Since some time the metaphor of logical space has been used to open new approaches to Hegel’s “Science of Logic”. Frequently it is noticed that in such an interpretation logical space must be understood as dynamic. However, as far as I can see, nobody has done yet the step to introduce the concept of logical time into the discussion, even though this step seems to suggest itself. The following contribution seeks to develop this thought and (...) arrives at some new conceptions, such as the curvature of logical space, logical actuality and semantic present, which may seem strange at first sight, but which follow consistently from the explication of the fundamental idea. The first aim in doing this is to broaden our conceptual repertoire do deal with Hegel’s Logic. This may open new perspectives of interpretation which may prove inspiring. Secondarily, the article also defends a systematic thesis which stands on its own and lays claim to truth. This claim goes far beyond a mere interpretation of Hegel and implies a fundamental critique of his philosophy. The comprehension of logical time-space leads to the requirement of logical chance event – and not only real chance. This goes against Hegel claim to absolute necessity in the dialectical development of his Logic and leads to a new philosophic comprehension of logic as such. (shrink)

In the present version of these lecture notes only a number of typos and a few glaring mistakes have been corrected. Thanks to Paul Dekker for his help in this respect. No attempt has been been made to update the original text or to incorporate new insights and approaches. For a more recent overview, see our ‘Questions’ in the Handbook of Logic and Language (edited by Johan van Benthem and Alice ter Meulen, Elsevier, 1997).

I try to lay bare some of the conceptual space in which one may be a Social Trinitarian. I organize the paper around answers to five questions. These are: (1) How do the three Persons of the Trinity relate to the Godhead? (2) How many divine beings or gods are there? (3) How many distinct centers of consciousness are there in the Godhead? (4) How many omnicompetent beings are there? (5) How are the Persons of the Trinity individuated? I (...) try to make clear costs and benefits of various answers to these questions. (shrink)

Philosophers have long been tempted by the idea that objects and properties are abstractions from the facts. But how is this abstraction supposed to go? If the objects and properties aren't 'already' there, how do the facts give rise to them? Jason Turner develops and defends a novel answer to this question: The facts are arranged in a quasi-geometric 'logical space', and objects and properties arise from different quasi-geometric structures in this space.

The paper applies the theory presented in A Formal Ontology of Situations (this journal, vol. 41 (1982), no. 4) to obtain a typology of metaphysical systems by interpreting them as different ontologies of situations. Four are treated in some detail: Hume's diachronic atomism, Laplacean determinism, Hume's synchronic atomism, and Wittgenstein's logical atomism. Moreover, the relation of that theory to the situation semantics of Perry and Barwise is discussed.

Review of "The Construction of Logical Space", by Augustin Rayo. Oxford: OxfordUniversity Press, 2013. Pp. xix+220. H/b$35.00.

In this article, I show and discuss the relevance of Wittgenstein's arguments as to the spatial structure of sight to recent issues in the philosophy of mind. The first, bearing upon the dimensionality of the manifolds at play in depiction, plays a critical role in Clark's attempt to provide an independent account ofqualiaand of their differentiative properties. The second, pertaining to the properly spatial structure formed by the data of sight, is explicitly appealed to in the debate on the realistic (...) character of any genuinely spatial scheme. I argue that if Wittgenstein rightly assumes that the simultaneous presence of sensible places in vision is a key condition for objectivity, he fails nevertheless to warrant the allegedly realistic character of the scheme employed in his own search for a phenomenological description of the visual field. (shrink)

No attempt has been been made to update the original text or to incorporate new insights and approaches. For a more recent overview, see our ‘Questions’ in the Handbook of Logic and Language (edited by Johan van Benthem and Alice ter Meulen, Elsevier, 1997).

This essay presents a heterodox reading of the issue of solipsism in Wittgenstein’s Tractatus Logico-Philosophicus, out of which the whole of the TLP can be re-read. Inspired by, though not dependent on, the themes of virtuality and singularity found in Deleuze’s ‘transcendental empiricism’, Wittgenstein’s concept of ‘logical space’ is here complexly related to the paradoxes of the ‘metaphysical subject’ and ‘solipsism,’ within which the strictures of sense are defined, and through which the logico-pictorial scaffolding of the TLP precipitates (...) its own systematic dissolution. It shows how nonsense envelopes not only not idle chatter, and metaphysical confusion, but sense itself. (shrink)

Customary interpretations state that Tractarian thoughts are pictures, and, a fortiori, facts. I argue that important difficulties are unavoidable if we assume this standard view, and I propose a reading of the concept taking advantage of an analogy that Wittgenstein introduces, namely, the analogy between thoughts and projective geometry. I claim that thoughts should be understood neither as pictures nor as facts, but as acts of geometric projection in logical space. The interpretation I propose thus removes the root (...) of the identified difficulties. Moreover, it allows important clarification concerning some central aspects of the Tractarian theory of representation, and it yields a unifying elucidation regarding Wittgenstein’s remarks on the solipsistic thesis. (shrink)

A logical space is a pair of a non-empty set A and a subset of . Since is identified with {0, 1} A and {0, 1} is a typical lattice, a pair of a non-empty set A and a subset of for a certain lattice is also called a -valued functional logical space. A deduction system on A is a pair (R, D) of a subset D of A and a relation R between A* and A. (...) In terms of these simplest concepts, a general framework for studying the logical completeness is constructed. (shrink)

This chapter is part of a project to collect David Lewis's correspondence explicitly on topics in the philosophy of religion and arrange major threads by topic, tying the correspondence to his published work. The chapter confines itself to only few letters on only a few topics. David's metaphysics sometimes takes the form of philosophical theology, especially in his correspondence about the free will theodicy. It presents selections of David's correspondence on topics in the philosophy of religion: a letter on evil, (...) specifically on the possibility of divine evil, evil perpetrated by God a letter on evil. The chapter concludes with a discussion of the place which, according to the author, God must have in David's logical space and also of the success of the many‐worlds theodicy that David briefly discusses. (shrink)

Abstract This paper discusses some recent work on the notion of possibility in Wittgenstein's Tractatus assessed by means of an interpretation of the notion put forward in Cerezo 2005. It argues that the proper way to understand the notion of possibility in the Tractatus must pay equal attention both to the picture theory and the truth-functions theory. From this perspective, through an examination of Peach's proposal (2007) it shows that the role played by the notion of logical space (...) in the determination of sense needs to be emphasized. In addition, the paper considers some consequences of the Tractarian notion of possibility, namely, the strong contingency of the world that it involves, which is revealed by the thinkability of logical space as empty envisaged by Wittgenstein in T 2.013, and also discusses the recent debate between Reinhardt (2005) and Geach (2006) on this issue. (shrink)

In The Construction of Logical Space, Agustín Rayo defends trivialism, according to which number-involving truths are trivially equivalent to other, non-number-involving truths; picturesquely, ‘I have five fingers on my hand’ and ‘the number of fingers on my hand is five’ express the same fact, but carved up in different ways. A single fact thus has multiple structures. I distinguish two ways this might go: on the deflationary picture, facts get their structures from our linguistic practices, while on an (...) inflationary picture, facts have multiple structures independently of language. I argue that Rayo’s view is best interpreted as deflationary. Thus interpreted, it blocks off an attractive solution to the old problems of intensionality. I further argue a that a semi-deflationary variant of Rayo’s view can make use of the attractive solution—but it thereby sacrifices the supposed mathematical benefits of trivialism. (shrink)

There are two ways of thinking about instants of time: "spatial" accounts emphasize the similarities between instants and places; "modal" accounts focus on the parallels between times and possible worlds. My aim in this paper is to draw attention to one respect in which times are more similar to possible worlds than they are to places.

In this article I offer a novel explanation of Wittgenstein’s claim, in his Tractatus, that to represent the logical form of a proposition would require our being positioned outside of logic. The account here presented aims to exploit a connection, widely noticed, between the logical forms of objects and those of the propositions in which the names of those objects figure. I show that the logical forms of propositions may, on Wittgenstein’s view, be identified with places in (...) logical space, and that places in logical space are reducible to the forms of both objects and their names. I argue, though, that according to Wittgenstein the representation of a proposition’s logical form would require the existence of a place in logical space not so reducible. I conclude that on Wittgenstein’s position, the attempt to represent logical forms cannot, therefore, succeed. (shrink)

In The Construction of Logical Space, Agustín Rayo defends trivialism, according to which number-involving truths are trivially equivalent to other, non-number-involving truths; picturesquely, ‘I have five fingers on my hand’ and ‘the number of fingers on my hand is five’ express the same fact, but carved up in different ways. A single fact thus has multiple structures. I distinguish two ways this might go: on the deflationary picture, facts get their structures from our linguistic practices, while on an (...) inflationary picture, facts have multiple structures independently of language. I argue that Rayo’s view is best interpreted as deflationary. Thus interpreted, it blocks off an attractive solution to the old problems of intensionality. I further argue a that a semi-deflationary variant of Rayo’s view can make use of the attractive solution—but it thereby sacrifices the supposed mathematical benefits of trivialism. (shrink)

It has been argued recently that classical theism and Lewisian modal realism are incompatible theses. The most substantial argument to this effect takes the form of a trilemma. It argues that no sense can be made of God’s being a necessary being in the modal realistic picture, on pain of, among other things, modal collapse. The question of this essay is: Is that so? My goal here is to detail the reasons that have been offered in support of this contention (...) and then defend the coherence of theistic modal realism from the trilemma. I call my reply to the argument an “Anselmian-Thomistic” defense, since it appeals to resources from classical medieval philosophy, especially from Anselm and Aquinas. (shrink)

To generalize as in [7] the constructions of [2] and [5], let L be a nondegenerate join-semilattice with unit. With A · B = {x ∨ y ∈ L : x ∈ A, y ∈ B} and A⊥ = {y ∈ L : x ∨ y = 1 for all x ∈ A}, the structure , ·,∪, ⊥ , L, ∅) is the algebra of subsets for L. Let R be the maximal ideals of L. Interpreting L as the totality (...) of elementary situations, and 1 ∈ L as the impossible one , the members of R will be called realizations, and R itself – the logical space associated with L. (shrink)

ABSTRACT This paper defends a controversial view about personal identity. It argues that it is possible to endorse both Phenomenalism and Materialism about persons. Phenomenalism is the view that personal identity is grounded in phenomenal consciousness. Materialism is the view that we are material objects. Many believe that the two views are incompatible. In this paper, I show that it is possible to accept both. I consider two objections against their combination—the argument from disembodiment and an important objection by Tim (...) Bayne. My responses are based on Kripke’s analysis of necessary a posteriori and contingent a priori statements. I make the case that both objections rest on different kinds of modal illusions. This strategy can be applied to other arguments, and the paper is intended to advocate a general approach to personal identity. (shrink)

En esta discusión abordo la hermenéutica analógica de Mauricio Beuchot comparándola con la hermenéutica filosófica de Hans-Georg Gadamer. Argumento que Beuchot vuelve a la idea clásica de la hermenéutica como método de interpretación y no la juzga, como Gadamer, como una fenomenología de la comprensión. Sin embargo, Beuchot no atiende las razones de Gadamer en contra de concebir la hermenéutica como una metodología. Si se considera como metodología centrada en la analogía, la hermenéutica analógica deja de lado otros recursos interpretativos (...) importantes. Finalmente, Beuchot adopta una teoría correspondentista de la verdad contra la que argumenta Gadamer y que es incompatible con una hermenéutica filosófica. In this paper I analyze Mauricio Beuchot's analogical hermeneutics by contrasting it with Hans-Georg Gadamer's philosophical hermeneutics. I argue that Beuchot goes back to the classical idea of hermeneutics as a method of interpretation, and does not see it, as Gadamer does, as a phenomenology of understanding. However, Beuchot does not address Gadamer's arguments against using hermeneutics as a methodology. Considered as a methodology centered on analogy, analogical hermeneutics overlooks other important interpretation resources. Finally, Beuchot adopts a correspondence theory of truth, which Gadamer objects and is incompatible with philosophical hermeneutics. (shrink)

This paper continues the work begun by Crispin Wright of identifying, articulating, and explaining the relations between various realist-relevant axes that emerge when it is conceded that any predicate capable of satisfying a small range of platitudes is syntactically and semantically adequate to count as a truth predicate for a discourse. I argue that the fact that a given discourse satisfies the three realist-relevant axes that remain if evidence-transcendent truth and reference to evidence-transcendent facts are ruled out by Dummettian meaning-theoretic (...) considerations is not sufficient for what I have elsewhere called “modest metaphysical realism.” I conclude that mind-independence marks yet another realist-relevant axis and explore the relationships between the proposed mind-independence axis and the realist-relevant axes identified by Wright. (shrink)

Probability measures can be constructed using the measure-theoretic techniques of Caratheodory and Hausdorff. Under these constructions one obtains first an outer measure over "events" or "propositions." Then, if one restricts this outer measure to the measurable propositions, one finally obtains a classical probability theory. What I argue is that outer measures can also be used to yield the structures of probability theories in quantum mechanics, provided we permit them to range over at least some unmeasurable propositions. I thereby show that (...) nonclassical probability theories can be seen to arise naturally within the framework of possible worlds semantics. (shrink)

The assumption that natural selection alone is sufficient to explain not only which traits get fixed in a population/species, but also how they develop, has been questioned since Darwin’s times, and increasingly in the last decades. Alternative theories, linked to genetic and phenotypic processes, or to the theory of complex systems, have been proposed to explain the rise of the phenotypic variety upon which natural selection acts. In this article, we illustrate the current state of the issue and we propose (...) a logical space based on phenotypic robustness that allows a classification of evolutionary phenomena and can provide a framework for unifying all these accounts. (shrink)

In sections 1 through 5, I develop in detail what I call the standard theory of worlds and propositions, and I discuss a number of purported objections. The theory consists of five theses. The first two theses, presented in section 1, assert that the propositions form a Boolean algebra with respect to implication, and that the algebra is complete, respectively. In section 2, I introduce the notion of logical space: it is a field of sets that represents the (...) propositional structure and whose space consists of all and only the worlds. The next three theses, presented in sections 3, 4, and 5, respectively, guarantee the existence of logical space, and further constrain its structure. The third thesis asserts that the set of propositions true at any world is maximal consistent; the fourth thesis that any two worlds are separated by a proposition; the fifth thesis that only one proposition is false at every world. In sections 6 through 10, I turn to the problem of reduction. In sections 6 and 7, I show how the standard theory can be used to support either a reduction of worlds to propositions or a reduction of propositions to worlds. A number of proposition-based theories are developed in section 6, and compared with Adams's world-story theory. A world-based theory is developed in section?, and Stalnaker's account of the matter is discussed. Before passing judgment on the proposition based and world-based theories, I ask in sections 8 and 9 whether both worlds and propositions might be reduced to something else. In section 8, I consider reductions to linguistic entities; in section 9, reductions to unfounded sets. After rejecting the possibility of eliminating both worlds and propositions, I return in section 10 to the possibility of eliminating one in favor of the other. I conclude, somewhat tentatively, that neither worlds nor propositions should be reduced one to the other, that both worlds and propositions should be taken as basic to our ontology. (shrink)

This is a review of 'The Facts in Logical Space' by Jason Turner.

Modal logicism is the view that a metaphysical possibility is just a non-absurd way for the world to be. I argue that modal logicists should see metaphysical possibility as "open ended'': any given possibilities can be used to characterize further possibilities. I then develop a formal framework for modal languages that is a good fit for the modal logicist and show that it delivers some attractive results.

In establishing unexpected cross-connections between physics, the theory of perception, and logic, Hyder also makes a valuable contribution to the history of ...

Wittgenstein’s atomist picture, as embodied in his Tractatus, is initially very appealing. However, it faces the famous colour-exclusion problem. In this paper, I shall explain when the atomist picture can be defended in the face of that problem; and, in the light of this, why the atomist picture should be rejected. I outline the atomist picture in Section 1. In Section 2, I present a very simple necessary and sufficient condition for the tenability of the atomist picture. The condition is: (...) logical space is a power of two. In Sections 3 and 4, I outline the colour-exclusion problem, and then show how the cardinality-condition supplies a response to exclusion problems. In Section 5, I explain how this amounts to a distillation of a proposal due to Moss, which goes back to Carruthers. And in Section 6, I show how all this vindicates Wittgenstein’s ultimate rejection of the atomist picture. The brief reason is that we have no guarantee that there are any solutions to a given exclusion problem but, if there are any, then there are far too many. (shrink)

I argue that Agustín Rayo’s symmetric ‘just is’ statements cannot be defined in terms of notions like essence, grounding or metaphysical truth-conditions. I go on to argue that one of these latter notions, which allow us to express an asymmetric relationship between facts, is needed to do some of the work that Rayo intends ‘just is’ statements to do, such as stating reductionist claims.

Gaining information can be modelled as a narrowing of epistemic space . Intuitively, becoming informed that such-and-such is the case rules out certain scenarios or would-be possibilities. Chalmers’s account of epistemic space treats it as a space of a priori possibility and so has trouble in dealing with the information which we intuitively feel can be gained from logical inference. I propose a more inclusive notion of epistemic space, based on Priest’s notion of open worlds (...) yet which contains only those epistemic scenarios which are not obviously impossible. Whether something is obvious is not always a determinate matter and so the resulting picture is of an epistemic space with fuzzy boundaries. (shrink)