Jacek Wawer

Jagiellonian University, Kraków

Metaphysics of Branching Possibilities

21 June 2019, 16:00

Faculdade de Letras de Lisboa

Sala Mattos Romão (Departamento de Filosofia)

Abstract: The model of so-called Branching-Time was introduced by Saul Kripke and Arthur Prior to investigate indeterminism and temporal asymmetry between “settled” past and “open” future. The model was often adopted for various formal (primarily semantic) purposes, but the proper philosophical interpretation of the model was usually highly underdeveloped. The purpose of the paper is to fill in the interpretative gap and analyze the structure underlying the branching model. I first observe that it is highly misleading to assume that the structure represents the branching of time. Such an understanding is open to many common sense and scientific objections. I argue that it is much more reasonable to understand the elements of the structure as branching possibilities. I then propose an account of the structure in fashion of genuine (or extreme) modal realism of David Lewis – as consisting of non-modal and non-tensed events. Many claims of branching theorists suggest such non-modal account of reality. In particular, their insistence that no particular modal viewpoint is privileged – which I call modal neutrality – is readily understood within the non-modal picture of branching. I propose, however, an interpretation of the branching structure that weds modal neutrality with modal primitivism. The idea is inspired by non-standard tense realism (non-standard A-theory) proposed by Kit Fine. I also outline a potential trap inherent in such an account of branching reality: an unskilful attempt to combine modal neutrality with modal primitivism might lead to an indefensible amalgam of ideas which Nuel Belnap dubbed the Thin Red Line.

Marco Ruffino

University of Campinas

Illocutionary Acts in Mathematics

24 June 2019, 11:00

Faculdade de Letras de Lisboa

Sala Mattos Romão (Departamento de Filosofia)

Abstract: Contemporary speech act theory was originally developed by Austin (1962) and further elaborated by Searle (1969, 1975, 1979) as an account of the illocutionary aspects of utterances in ordinary language. In particular, this theory searched for a foundational account of the linguistic dimension of human action. Later it found widespread application in the philosophy of mind, philosophy of law and, more recently, in the foundation of social sciences. However, in the philosophy of mathematics and of logic very little attention has been paid to pragmatic phenomena; indeed, pragmatic aspects of mathematical language are almost universally ignored. The purpose of this paper is to apply the machinery of contemporary speech act theory (especially Searle and Vanderveken (1985)) to the essential aspects of mathematics as a science. This hypothesis should not be understood as a defense of an anti-realist ontology of mathematical entities or propositions. Indeed, as I shall argue, this hypothesis is largely independent of any such ontology. Even if one adopts a strict realist view of mathematical entities, the discovery of these entities and of their structure depends largely on some illocutionary acts. It should also not be confounded with the trivial claim that communication among mathematicians is done in part using natural language and, as such, it is impregnated with illocutionary acts (questions, assertions, promises, praises, invitations, etc.).; the working hypothesis is that even at the level of highly abstract and formalized language there are some essential illocutionary acts as well as some illocutionary force indicators.

Marco Ruffino

University of Campinas

Contingent A Priori Truths and Performatives

19 June 2019, 16:00

Faculdade de Letras de Lisboa

Sala Mattos Romão (Departamento de Filosofia)

Abstract: My primary goal in this paper is to defend the plausibility of Kripke’s (1980) thesis that there are contingent a priori truths, and to fill out some gaps in Kripke’s own account of these truths. But the strategy here adopted is, to the best of my knowledge, still unexplored and different from the one adopted both by Kripke himself and by his critics. I first argue that Kripke’s examples of such truths can only be legitimate if seen as introduced by performative utterances (in Austin’s (1962) sense). And, if this is so, we can apply the machinery of illocutionary act theory (especially Searle and Vanderveken (1985)) to these utterances to explain how one can have a priori knowledge of some contingent facts generated by the utterances themselves. I shall argue that the overall strategy can fill out two gaps in Kripke’s original account: first, we can explain the nature of the truth-makers of contingent a priori truths (they are institutional facts in Searle’s (1969) sense, broadly conceived) and, second, we can explain how contingent a priori knowledge can be transmitted from one speaker to another (via the notion of illocutionary commitment).

SEMINAR SERIES IN ANALYTIC PHILOSOPHY
2018-19: Session 26
Knowledge of Future Contingents
Andrea Iacona
University of Turin
14 June 2019, 16:00
Faculdade de Letras de Lisboa
Sala Mattos Romão (Departamento de Filosofia)
Abstract: This talk addresses the question whether future contingents are knowable, that is, whether we can know that things will go a certain way even though it is possible that things will not go that way. First I will consider a long-established line of thought that implies a negative answer, and draw attention to some endemic problems that affect its credibility. Then I will sketch an alternative line of thought that prompts a positive answer. The idea that future contingents are knowable proves to be harmless, once its implications are properly spelled out.

Christian Wuthrich

University of Geneva

Does Spacetime Functionalism Have to be Universal?

(based on joint work with Vincent Lam)

 

7 June 2019, 16:00

Faculdade de Letras de Lisboa

Sala Mattos Romão (Departamento de Filosofia)

Abstract: In past work, Lam and I have defended spacetime functionalism as a response to the problem of the emergence of spacetime in quantum theories of gravity. But can spacetime functionalism be such a local response to a specific problem in one class of physical theories? One might think not, at least not if held jointly with a sufficiently strong version of scientific realism: if we accept that quantum gravity implies that spacetime is at best emergent, then we should have been antirealists about it all along, i.e., already in earlier theories such as general relativity. A “pessimistic metainduction” thus appears to force the joint commitment to scientific realism and to spacetime functionalism to render the latter a universal template, rather than a local solution to a specific problem. In my talk, I will resist this universalism, and argue that a local spacetime functionalism is compatible with an appropriate form of scientific realism.

Karen Crowther

University of Geneva

Levels of Fundamentality in the Metaphysics of Physics

31 May 2019, 16:00

Faculdade de Letras de Lisboa

Sala Mattos Romão (Departamento de Filosofia)

Abstract: Judging by how physicists use the term, there are many different conceptions of what it means for a physical theory to be ‘fundamental’. Yet, it has been argued that none of these imply metaphysical fundamentality. Here, I argue that there is a plausible sense of relative fundamentality in physics that corresponds to a fairly standard conception of relative fundamentality according to metaphysics. I discuss what the implications of this are for our understanding of ‘levels’ of fundamentality and explanation.

Yemima Ben-Menahem

Hebrew University of Jerusalem

Lawlessness and (a kind of) Freedom

24 May 2019, 16:00

Faculdade de Letras de Lisboa

Sala Mattos Romão (Departamento de Filosofia)

Abstract: The literature on freedom recognizes two different (and mutually exclusive) understandings of freedom—libertarian freedom and compatibilism. This paper offers a third option—lawlessness. It discusses three forms of lawlessness, all of which are compatible with determinism. The first concerns the irreducibility, within science, of higher level concepts to the level of fundamental physics. The second stems from the Kolmogorov-Chitin redefinition of randomness. The third is a variation on Davidson’s anomalous monism. As a result, the paper suggests a new kind of freedom—freedom from the law—which differs from libertarian freedom but is superior to compatibilism.

Centro de Filosofia da Universidade de Lisboa

LanCog Group (Language, Mind and Cognition Research Group)

Centro de Matemática, Aplicações Fundamentais e Investigação Operacional

CMAF-CIO

 

Hartry Field

New York University

Generalizing Fuzzy Logic for Semantic Paradoxes (and Vagueness)

20 May 2019, 16:00

Faculdade de Ciências da Universidade de Lisboa

Building C6, 2nd floor, room 6.2.33

Abstract: Lukasiewicz continuum-valued logic has been popular in dealing with vagueness, and prominent logicians (e.g. Thoralf Skolem and C. C. Chang) have been very interested in its application to the semantic, property-theoretic and set-theoretic paradoxes. But it isn’t ultimately workable for either. This talk will sketch how to generalize it to make it work (not for set theory, because of extensionality, but for truth and properties, and also for vagueness). The resulting theory is more powerful than Kripke’s in that it treats conditionals and restricted (as well as unrestricted) quantifiers. I’ll avoid technical details, but give enough of the idea so that those technically inclined shouldn’t have much problem filling them in. There will also be a bit of discussion of why we need two kinds of conditionals.

Free Attendance

For further information, please write to c.filosofia@letras.ulisboa.pt or cmafcio@fc.ul.pt

Hartry Field

New York University

Epistemology from a “Naturalistic” (but not Reliabilist) Perspective

17 May 2019, 16:00

Faculdade de Letras de Lisboa

Sala Mattos Romão (Departamento de Filosofia)

Abstract: I’ll advocate an obvious-sounding approach to epistemology, that involves developing general models of possible epistemic practices and critically evaluating which of those practices are likely to do best at achieving various truth-oriented goals. Despite its obviousness, there is an apparently serious problem with this idea, a generalization of the one in Lewis’s discussion of immodest inductive methods: each practice seems bound to evaluate itself as best, in which case the “critical evaluation” cuts no ice and one just ends up with whatever practice one starts with. A lot of the paper will be a critique of the line of thought behind the apparent problem, and of a certain picture of “epistemic rules” on which it rests. Once we’ve cleared away the problem, we can see the virtues of the approach, including the fact that it avoids unproductive issues that arise from fetishizing epistemic vocabulary such as knowledge and justification. The critical evaluation in the approach is truth-oriented, but avoids the many problems of reliabilism: both its refusal to recognize any “internalist” considerations and the fact that no notion of reliability seems adequate to encompass all the different factors we want our inductive practices to satisfy. The methodology fits best with a kind of normative anti-realism, about which I hope to say a bit at the end, and which provides another respect in which the approach is “naturalistic”.