Modal Fictionalism and Compositionality

Modal fictionalists propose to defuse the unwanted ontological commitments of modal realism by treating modal realism as a fictional story, and modal assertions as assertions, prefixed by a fictionalist operator, that something is true in that story. However, consideration of conditionals with modal antecedents raises the problem ofembedding, which shows that the simple prefixing strategy cannotsucceed. A compositional version of the fictionalist strategy isdeveloped and critiqued, and some general semantic morals aredrawn from the failures of both strategies.     

Inclusionism and the Problem of Unmarried Husbands

I discuss a modification of Lewisian modal realism called ‘inclusionism’. Inclusionism is the thesis that some worlds contain other worlds as proper parts. Inclusionism has some attractive consequences for theories of modality. Josh Parsons, however, has raised a problem for inclusionism: the problem of unmarried husbands. In this paper I reply to this problem. My strategy is twofold: first I claim, pace Parsons, that it is not clear why the inclusionist cannot avail herself of an obvious solution to the problem; and second, I argue that even if there is no available solution, the same problem also afflicts Lewis’ original theory. Therefore, even if the problem remains unsolved, we have not been given any reason to think that an inclusionist version of Lewisian realism is worse than the original.     

Fiction: Impossible!

I argue that modal realism is unable to account for fictional discourse. My starting point is an overview of modal realism. I then present a dilemma for modal realism regarding fictional characters. Finally, I provide responses to both horns of the dilemma, one motivating modal dimensionalism, the other motivating a disjunctive analysis of modality.     

The Structural Metaphysics of Quantum Theory and General Relativity

The paper compares ontic structural realism in quantum physics with ontic structural realism about space–time. We contend that both quantum theory and general relativity theory support a common, contentful metaphysics of ontic structural realism. After recalling the main claim of ontic structural realism and its physical support, we point out that both in the domain of quantum theory and in the domain of general relativity theory, there are objects whose essential ways of being are certain relations so that these objects do not possess an intrinsic identity. Nonetheless, the qualitative, physical nature of these relations is in the quantum case (entanglement) fundamentally different from the classical, metrical relations treated in general relativity theory.     

On Quantitative and Qualitative Parsimony

The distinction between quantitative and qualitative parsimony is supposed to allow David Lewis to dismiss one of the charges against his modal realism: that is, the charge of bloated ontology. The aim of this paper is to undermine Lewis's response to this objection. In order to do this, a distinction between multipliable and nonmultipliable objects is introduced. Based on this it is argued that the acceptance of Lewis's response requires one to believe in modal realism in the first place—that is, one has to believe in the view that the existence of nonactual spatiotemporal worlds does not affect the quality of the ontological commitment. Although the paper focuses on the problem of the metaphysics of possible worlds, this should be regarded merely as a case study. Accordingly, the results of this analysis should find applications in other metaphysical debates as well.     

Is Everything A World?

This paper discusses “inclusionism” in the context of David Lewis’s modal realism (and in the context of parasitic accounts of modality such as\ John Divers’s agnosticism about possible worlds). This is the doctrine that everything is a world. I argue that this doctrine would be beneficial to Divers-style agnosticism; that it suggests a reconfiguration of the concept of actuality in modal realism; and finally that it suffers from an as-yet unsolved difficulty, the problem of the unmarried husbands. This problem also shows that Stephen Yablo’s analysis of “intrinsic” is inadequate. Thanks to Philip Bricker, Ross Cameron, Daniel Nolan, John Divers, Kit Fine, Kris McDaniel, Augustin Rayo, Steve Yablo, to participants in the Arche modality seminar, University of St Andrews, and to the delegates of the APA Pacific Division Conference 2005.     

Hegel's Essentialism. Natural Kinds and the Metaphysics of Explanation in Hegel's Theory of ‘the Concept’

Several recent interpretations see Hegel's theory of the Concept as a form of conceptual realism, according to which finite reality is articulated by objectively existing concepts. More precisely, this theory has been interpreted as a version of natural kind essentialism, and it has been proposed that its function is to account for the possibility of genuine explanations. This suggests a promising way to reconstruct the argument that Hegel's theory of objective concepts is based on—an argument that shows that the possibility of explanation rests on metaphysical preconditions and that natural kind essentialism gives the only adequate account of those preconditions. But in order for such a reconstruction to be successful, one needs to spell out the metaphysical features in virtue of which Hegelian natural kinds can account for the possibility of explanation. The article takes up this challenge. It offers the first detailed analysis of the modal fine‐structure of Hegel's natural kind essentialism and shows how Hegel's position, thus understood, provides the details needed to complete the explanation‐based argument.     

The Model Theoretic Argument, Indirect Realism, and the Causal Theory of Reference Objection

Abstract: Hilary Putnam has reformulated his model-theoretic argument as an argument against indirect realism in the philosophy of perception. This new argument is reviewed and defended. Putnam's new focus on philosophical theories of perception (instead of metaphysical realism) makes better sense of his previous responses to the objection from the causal theory of reference. It is argued that the model-theoretic argument can also be construed as an argument that holders of a causal theory of reference should adopt direct realism in the philosophy of perception.     

Wavelength Theory of Colour Strikes Back: The Return of the Physical

There have been a number of criticisms, based on visual processes, of the Australian view that colour is an objective property of the world. These criticisms have led to subjective theories about colour. These visual processes (metamers, retinex theory, opponent processes, simultaneous contrast, colour constancy, subjective colours) have been examined and it is suggested that they do not carry their supposed critical weight against an objective theory. In particular, it is argued that metamers don't occur in nature and primate colour vision evolved without metamers. Thus normal colour vision occurs without the problem of metamers. This argument, in conjunction with evidence against the critical roles of opponent processes and retinex theory in colour vision, is taken to suggest that colour can be given a photon energy/wavelengthrealism explanation. This proposal allows an account of the many microstructural bases of colour generation put forward by Nassau (1983). It is argued that neither disjunctive realism or reflectance realism are adequate objective explanations of colour.     

Modal Realism with Modal Tense 1

Modal realists should fashion their theory by postulating and taking seriously the modal equivalent of tense, or modal tense. This will give them a uniform way to respond to five different objections, one each by Skyrms, Quine, and Peacocke, and two by van Inwagen, and suggest a non-Lewisian path to modal realism.     

Underdetermination, Holism and the Theory/Data Distinction

I examine the argument that scientific theories are typically 'underdetermined' by the data, an argument which has often been used to combat scientific realism. I deal with two objections to the underdetermination argument: (i) that the argument conflicts with the holistic nature of confirmation, and (ii) that the argument rests on an untenable theory/data dualism. I discuss possible responses to both objections, and argue that in both cases the proponent of underdetermination can respond in ways which are individually plausible, but that the best response to the first objection conflicts with the best response to the second. Consequently underdetermination poses less of a problem for scientific realism than has often been thought.     

The Place of Semantic Theory

Abstract: Some twenty years since its publication Putnam's model‐theoretic argument is still much discussed. The present paper aims to defend a reconstruction of the argument but begins by attempting to clarify the form of the argument. Usually, and with good textual grounds, the argument is treated as a reductio argument against metaphysical realism. I argue instead that it should be treated as developing a paradox. I go on to claim that the most promising response to this paradox is to be able to provide a theory of (Fregean) sense, in the style recommended by Dummett. So, according to this reasoning, the argument is not an argument against metaphysical realism but an argument against positions which reject the notion of sense.     

Explaining the Success of Science: Kuhn and Scientific Realists

In this essay, I critically evaluate the approaches to explaining the success of science in Kuhn and the works of inference-to-the-best-explanation scientific realists. Kuhn’s challenge to realists, who invoke the truth of theories to explain their success, is two-fold. His paradigm-account of success confronts realists with the problem of theory change, and the historical fact of successful theories later rejected as false. Secondly, Kuhn’s account of the success of science has no need to bring truth into the explanation. In turn, I argue that weakness in Kuhn and the prevailing forms of scientific realism motivate a better account of realism which I characterize as ‘best current theory realism’ and defend against the pessimistic meta-induction and the problem of theory-change. This realism argues that the best explanation of the success of current and past scientific theories only requires the simple claim that our best current theories are true. Kuhn’s account can explain how normal science succeeds but cannot account for why its problem solutions work where they do and why they fail for other puzzles.     

Mind-World Identity Theory and Semantic Realism: Haldane and Boulter on Aquinas

Stephen Boulter, in The Philosophical Quarterly , 48 (1998), pp. 504–13, attacks John Haldane's proposed account of the relationship between mind and world based on Aquinas' theory of cognition. Boulter argues against Haldane's attempt to square metaphysical realism with semantic anti-realism. I argue that even if metaphysical realism and a full-bodied semantic anti-realism may be incompatible, from the stance of the mind-world identity theory, one may nevertheless maintain metaphysical realism together with the negation of semantic realism. I suggest that this is what Haldane actually claimed, and moreover that Aquinas would have accepted it. Aquinas' analogy-based semantics enlarges the recognitional capacities of speakers, and one's capacity to recognize a fact empirically is different from one's capacity to form thoughts about a fact.     

Open future and modal anti-realism

Open future is incompatible with realism about possible worlds. Since realistically conceived (concrete or abstract) possible worlds are maximal in the sense that they contain/represent the full history of a possible spacetime, past and future included, if such a world is actual now, the future is fully settled now, which rules out openness. The kind of metaphysical indeterminacy required for open future is incompatible with the kind of maximality which is built into the concept of possible worlds. The paper discusses various modal realist responses and argues that they provide ersatz openness only, or they lead to incoherence, or they render the resulting theory inadequate as a theory of modality. The paper also considers various accounts of the open future, including rejection of bivalence, supervaluationism, and the ‘thin red line’ view (TRL), and claims that a version of (TRL) can avoid the incompatibility problem, but only at the cost of deflating the notion of openness.     

Propositions, Sets, and Worlds

If we agree with Michael Jubien that propositions do not exist, while accepting the existence of abstract sets in a realist mathematical ontology, then the combined effect of these ontological commitments has surprising implications for the metaphysics of modal logic, the ontology of logically possible worlds, and the controversy over modal realism versus actualism. Logically possible worlds as maximally consistent proposition sets exist if sets generally exist, but are equivalently expressed as maximally consistent conjunctions of the same propositions in corresponding sets. A conjunction of propositions, even if infinite in extent, is nevertheless itself a proposition. If sets and hence proposition sets exist but propositions do not exist, then whether or not modal realism is true depends on which of two apparently equivalent methods of identifying, representing, or characterizing logically possible worlds we choose to adopt. I consider a number of reactions to the problem, concluding that the best solution may be to reject the conventional model set theoretical concept of logically possible worlds as maximally consistent proposition sets, and distinguishing between the actual world alone as maximally consistent and interpreting all nonactual merely logically possible worlds as submaximal. I am grateful to the Netherlands Institute for Advanced Study in the Humanities and Social Sciences (NIAS), Royal Netherlands Academy of Arts and Sciences (KNAW), for supporting this among related research projects in philosophical logic and philosophy of mathematics during my Resident Research Fellowship in 2005-2006.     

Informational Realism and World 3

This paper takes up a suggestion made by Floridi that the digital revolution is bringing about a profound change in our metaphysics. The paper aims to bring some older views from philosophy of mathematics to bear on this problem. The older views are concerned principally with mathematical realism—that is the claim that mathematical entities such as numbers exist. The new context for the discussion is informational realism, where the problem shifts to the question of the reality of information. Mathematical realism is perhaps a special case of informational realism. The older views concerned with mathematical realism are the various theories of World 3. The concept of World 3 was introduced by Frege, whose position was close to Plato’s original views. Popper developed the theory of World 3 in a different direction which is characterised as ‘constructive Platonism’. But how is World 3 constructed? This is explored by means of two analogies: the analogy with money, and the analogy with meaning, as explicated by the later Wittgenstein. This leads to the development of an account of informational realism as constructive Aristoteliansim. Finally, this version of informational realism is compared with the informational structural realism which Floridi develops in his 2008 and 2009 papers in Synthese. Similarities and differences between the two positions are noted.     

Scientific Realism and Quantum Mechanics: Revisiting a Controversial Relation

The article examines the controversial relation of scientific realism with quantum mechanics. To this end, two distinct discussions are invoked: the discussion about ‘realism’ in the context of quantum mechanics and the discussion about ‘scientific realism’ in the context of the general philosophy of science. The aim is to distinguish them in order, first, to argue that the former—revolving around ‘local realism’ and the theorems of Bell and Kochen–Specker—unjustifiably identifies realism with features of a particular worldview, and thereby fosters the impression that the failure of ‘local realism’ in quantum experiments constitutes a failure of scientific realism too; and, second, in light of the latter discussion, to claim that scientific realism and quantum mechanics can be compatible—there is ground for dealing with quantum measurement simply as a physical mind-independent interaction. Therefore, a realist approach to the theory is possible despite its notorious measurement problem, even if the issue of its interpretation is still disputed.     

A Case for Modal Fragmentalism

Philosophia - The idea of fragmentalism has been proposed by Kit Fine as a non-standard view of tense realism. This paper examines a modal version of the view, called modal fragmentalism, which...