Online research in philosophy

A powerful challenge to some highly influential theories, this book offers a thorough critical exposition of modal realism, the philosophical doctrine that many possible worlds exist of which our own universe is just one. Chihara challenges this claim and offers a new argument for modality without worlds.

In this paper I argue that Modal Realism, the thesis that there exist non-actual possible individuals and worlds, can be made compatible with Metaphysical Nihilism, the thesis that it is possible that nothing concrete exists. Modal Realism as developed by Lewis rules out the possibility of a world where nothing concrete exists and so conflicts with Metaphysical Nihilism. In the paper I argue that Modal Realism can be modified so as to be compatible with Metaphysical Nihilism. Such a modification makes Modal Realism neither incur further theoretical costs nor lose its theoretical benefits. Thus such a modification constitutes an improvement of Modal Realism.

Modal realism -- Time, space, world -- Existence -- Actuality -- Modal realism and modal tense -- Transworld individuals and their identity -- Existensionalism -- Impossibility -- Proposition and relief -- Fictional worlds -- Epistemology.

to use David Chalmers's jargon) claim that though zombies are conceivable, they are not metaphysically possible. This article calls this position regarding the relation between metaphysical and epistemic modality "modal autonomism," as opposed to the "modal rationalism" endorsed by David Chalmers and Frank Jackson, who insist on a deep link between the two forms of modality. This article argues that the defense of modal rationalism presented in Chalmers and Jackson (2001) begs the question against the type-B materialist/modal autonomist. The argument proceeds as follows. Modal rationalists claim that for all nonphenomenal macro properties, the appropriate supervenience conditional is both necessary and a priori. Hence, type-B materialists must engage in special pleading when they claim that the relevant supervenience conditional for phenomenal properties, expressing the supervenience of the phenomenal on the physical, is necessary but not a priori. However, what Chalmers and Jackson demonstrate, if anything, is that the conditional that includes all the microphysical plus the phenomenal in the antecedent, and nonphenomenal macro facts (such as facts about water and other natural kinds, among other things) in the consequent, is a priori. The question arises why, since facts about water and the like do not metaphysically supervene on the phenomenal facts, is it appropriate to include the phenomenal facts in the antecedent of the relevant supervenience conditional. This article argues for the following claims: First, that it's crucial to the general semantic framework Chalmers and Jackson defend that they do include the phenomenal facts in the supervenience conditional; without them, the conditional would not be a priori. Second, that the only way to argue from the a priori character of these conditionals to the applicability of modal rationalism to the nonphenomenal cases is to rely either on modal rationalism itself or on the denial of type-B materialism. Obviously, in the context of this argument, either way would beg the question. CiteULike Connotea Del.icio.us Digg Reddit Technorati What's this?

The paper argues against Peacocke's moderate rationalism in modality. In the first part, I show, by identifying an argumentative gap in its epistemology, that Peacocke's account has not met the Integration Challenge. I then argue that we should modify the account's metaphysics of modal concepts in order to avoid implausible consequences with regards to their possession conditions. This modification generates no extra explanatory gap. Yet, once the minimal modification that avoids those implausible consequences is made, the resulting account cannot support Peacocke's moderate rationalism.

I present a case for a rapprochement between aspects of rationalism and scientific realism, by way of a general framework employing modal epistemology and elements of 2-dimensional semantics (2DS). My overall argument strategy is meta-inductive: The bulk of this paper establishes a “base case,” i.e., a concretely constructive example by which I demonstrate this linkage. The base case or constructive example acts as the exemplar for generating, in a constructively ‘bottom-up’ fashion, a more generally rigorous case for rationalism-realism qua modal epistemology. The exemple I choose in D. Chalmers’ (2002) modal rationalism and R. Giere’s (1985, 1988) constructive realism. I show by way of a thorough analysis how Giere’s claims concerning modal scope are characterized as instances of Chalmers’ modal rationalism, both weak and strong. In essence, as I demonstrate via Chalmers’ notions, ceteris paribus the constructive realist ultimately opts for a comparatively wider gate, characterized by modal reasoning, to lead from the rooms of conceivability qua thought experiments and models, to the pastures of metaphysical possibility. Chalmers likewise tries to erect such a wider gate, in his general conceivability-possibility theses. Anti-realists, on the other hand, see a narrower passage and my contention herein is that they suffer from modal myopia, which hopefully the ‘corrective vision’ of Chalmers’ modal rationalism can restore. In the introduction and concluding sections I sketch out suggestions of constructing ‘inductive steps’ from my base case, to generate more extensively general claims regarding realism qua rationalism.

It is commonly supposed that metaphysical modal claims are to be evaluated with respect to a single domain of possible worlds: a claim is metaphysically necessary just in case it is true in every possible world, and metaphysically possible just in case it is true in some possible world. We argue that the standard understanding is incorrect; rather, whether a given claim is metaphysically necessary or possible is relative to which world is indicatively actual. We motivate our view by attention to discussions in Salmon 1989 and Fine 2005, in which various data are taken to support rejecting the transitivity of accessibility (Salmon) and modal monism (Fine); we argue that relativized metaphysical modality can accommodate these data compatible with both standard modal logic(s) and modal monism. Noting an analogy with two-dimensional semantics, we argue that metaphysical modality has a complex structure, reflecting what is counterfactually possible, relative to each indicatively actual world. In arguing for the need for relativization, we are broadly on the same side as Crossley and Humberstone (1977) and Davies and Humberstone (1979); our contribution here is, first, to offer distinctively metaphysical reasons for relativization, and second, to show that relativization can be incorporated in ways minimally departing from standard modal logic(s).

Modality and Supervenience

According to the thesis of modal supervenience it is impossible that two objects be alike in their actual properties but differ in their modal properties. Some have argued that the concept of supervenience is inapplicable to the modal-actual case. Some have argued that the thesis of modal supervenience is trivially true. These arguments are refuted; a thesis of the supervenience of the modal on the actual is meaningful and nontrivial. The significance of the thesis is nevertheless limited by the problem of finding a nonmodal specification for the purported subvenient properties.

The paper begins with a clarification of the notions of intuition (and, in particular, modal intuition), modal error, conceivability, metaphysical possibility, and epistemic possibility. It is argued that two-dimensionalism is the wrong framework for modal epistemology and that a certain nonreductionist approach to the theory of concepts and propositions is required instead. Finally, there is an examination of moderate rationalism.

The article argues against attempts to combine ontological realism about modality with the rejection of modal rationalism and it suggests that modal realism requires (at least a weak form of) modal rationalism. /// El artículo da argumentos en contra de que se intente combinar el realismo ontológico sobre la modalidad con el rechazo del racionalismo modal y sugiere que el realismo modal exige (por lo menos una forma débil de) racionalismo modal.