Rational Reasons, Counterfactual Statements and “Impossible Worlds” in the Philosophical Justifications of Thought Experiments

In his theory of natural laws David Lewis rejects the authenticity of impossible worlds on the grounds that the contradiction contained within his modifier "in (the world) w" is tantamount to a contradiction in the whole theory, which seems unacceptable. At the same time, in philosophical discourse very often researchers use counterfactual situations and thought experiments with impossible events and objects. There is a need to apply the theory of worlds to genuine, concrete, but impossible worlds. One way to do this is to reject Lewis's classical negation on the grounds that it leads to problems of completeness and inconsistency inside the worlds. The proposed extension for impossibility is compatible with Lewis's extensional metaphysics, although it leads to some loss for description completeness in semantics.

Dreams of a Final Theory T

The grander metaphysical schemes popular in Hertz’s era often suppressed conceptual innovation in manifestly unhelpful ways. In counterreaction, Hertz and his colleagues stressed the raw pragmatic advantages of “good theory” considered as a functional whole and rejected the armchair meditations upon individual words characteristic of the metaphysical imperatives they spurned. Rudolf Carnap’s later rejection of all forms of “metaphysics” attempts to broaden these methodological tenets to a wider canvas. In doing so, the notion of an integrated, axiomatizable “theory” became the shaping tenet within our most conception of how the enterprise of “rigorous conceptual analysis” should be prosecuted. Although Carnap hoped to suppress all forms of metaphysics, large and small, through these means, in more recent times, closely allied veins of “theory T thinking” have instead encouraged a revival of grand metaphysical speculation that embodies many of the suppressive doctrines that Hertz’s generation rightly resisted (I have in mind the school of “analytic metaphysics” founded by David Lewis). The proper corrective to these inflated ambitions lies in directly examining the proper sources of descriptive effectiveness in the liberal manner of a multiscalar architecture.

Contra a noção de parte formal: Uma resposta a Kathrin Koslicki

Em seu livro de 2008, A estrutura dos objetos, Kathrin Koslicki defende uma teoria mereológica de cunho aristotélico para descrever a natureza dos objetos concretos. Tal teoria tem como coração a ideia de que objetos compostos são fusões de partes materiais e partes formais, ou seja, ela é uma espécie de neo-hilemorfismo. A principal motivação para a adoção de tal tese é se opor a certas teorias de composição, principalmente o universalismo mereológico, defendido por David Lewis (1986 e 1991). Entretanto, pretendo defender que nenhum dos argumentos de Koslicki é satisfatório para a postulação das partes formais. Isso porque os motivos que a levam ao comprometimento com essas entidades não apenas são injustificados, mas também é possível resolver os problemas levantados pela autora sem o apelo à própria noção de parte formal.

Structural Humility

In this article I discuss various humility theses about individuals and intrinsic properties as discussed by authors such as David Lewis. I argue that we should accept a similar humility thesis about the world’s space-time structure regardless of which metaphysics of space-time we accept. I argue this undercuts some important motivations opting in for an ontic structural realist metaphysic.

Does Lewis’ Theory of Causation Permit Time Travel?

David Lewis aimed to give an account of causation, and in particular, a semantics for the counterfactuals to which his account appeals, that is compatible with backwards causation and time travel. I will argue that he failed, but not for the reasons that have been offered to date, specifically by Collins, Hall and Paul and by Wasserman. This is significant not the least because Lewis’ theory of causation was the most influential theory over the last quarter of the 20th century; and moreover, Lewis’ spirited defence of time travel in the 1970s has shaped philosophers’ approach to time travel to this day.

The Metaphysics of Theism: A Classical and Neo-Classical Synthesis

This article aims to provide a metaphysical elucidation of the notion of Theism and a coherent theological synthesis of two extensions of this notion: Classical Theism and Neo-Classical Theism. A model of this notion and its extensions is formulated within the ontological pluralism framework of Kris McDaniel and Jason Turner, and the (modified) modal realism framework of David Lewis, which enables it to be explicated clearly and consistently, and two often raised objections against the elements of this notion can be successfully answered.

Fictional truth

A well-known theory about under which circumstances a statement is true in a fiction is the Reality Principle (RP), which originates in the work of David Lewis: “(RP) Where p1…pn are the primary fictional truths of a fiction F, it is true in F that q iff the following holds: were p1…pn the case, q would have been the case” (Walton 1990, 44). RP has been subjected to a number of counterexamples, up to a point where, in the words of Stacie Friend (2017, 33), “it is widely recognized that the Reality Principle […] cannot be a universal inference rule for implied story-truths”. This chapter argues that the strength of these counterexamples is widely overestimated, and that they do not, on closer scrutiny, constitute reasons for rejecting RP.

On the generation of content

This chapter explores the view that the contents of fictions and non-fictions are generated in the same way. It advocates a general principle of content generation which extends the account of fictional truths proposed by David Lewis. It is argued that, in generating the contents of fictions and non-fictions, the same issues arise and they may be dealt with in the same way. The proposal rests on Stalnaker's view that the assumptions shared by the participants in a conversational exchange provide the material out of which propositions are constructed. The idea underlying the account is that the communicative exchange involved in an author's producing a work for an audience, whether the work is fictive or non-fictive, is no different in principle from communicative exchanges in conversations. Differences in content related to fictional vs. non-fictional status are argued to depend on the role that conventions play in generating implicit truths in both fictive and non-fictive works.

Another way to look at counterfactuals

Counterfactuals such as If the world did not exist, we would not notice it have been a challenge for philosophers and linguists since antiquity. There is no generally accepted semantic analysis. The prevalent view, developed in varying forms by Robert Stalnaker, David Lewis, and others, enriches the idea of strict implication by the idea of a “minimal revision” of the actual world. Objections mainly address problems of maximal similarity between worlds. In this paper, I will raise several problems of a different nature and draw attention to several phenomena that are relevant for counterfactuality but rarely discussed in that context. An alternative analysis that is very close to the linguistic facts is proposed. A core notion is the “situation talked about”: it makes little sense to discuss whether an assertion is true or false unless it is clear which situation is talked about. In counterfactuals, this situation is marked as not belonging to the actual world. Typically, this is done in the form of the finite verb in the main clause. The if-clause is optional and has only a supportive role: it provides information about the world to which the situation talked about belongs. Counterfactuals only speak about some nonactual world, of which we only know what results from the protasis. In order to judge them as true or false, an additional assumption is required: they are warranted according to the same criteria that warrant the corresponding indicative assertion. Overall similarity between worlds is irrelevant.