Fabrice Correia and Sven Rosenkranz As Time Goes By Eternal Facts in an Ageing Universe mentis PADERBORN
Gedruckt mit Unterstützung des Ministerio de Ciencia e Innovación, Madrid (FFI2008-06153), und der Faculté des Lettres, Université de Genève (Fabrice Correias overheads funds). Cover Illustration: Artur Serra Costa, Untitled, 2011, digital photograph Courtesy of the artist Bibliografische Information Der Deutschen Nationalbibliothek Die Deutsche Nationalbibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über http://dnb.d-nb.de abrufbar. Gedruckt auf umweltfreundlichem, chlorfrei gebleichtem und alterungsbeständigem Papier ISO 9706 2011 mentis Verlag GmbH Schulze-Delitzsch-Straße 19, D-33100 Paderborn www.mentis.de Alle Rechte vorbehalten. Dieses Werk sowie einzelne Teile desselben sind urheberrechtlich geschützt. Jede Verwertung in anderen als den gesetzlich zulässigen Fällen ist ohne vorherige Zustimmung des Verlages nicht zulässig. Printed in Germany Einbandgestaltung: Anne Nitsche, Dülmen (www.junit-netzwerk.de) Satz: Rhema Tim Doherty, Münster [ChH] (www.rhema-verlag.de) Druck: AZ Druck und Datentechnik GmbH, Kempten ISBN 978-3-89785-748-3
Preface In the beginning there was the idea, which quickly took shape, that there is an intuitively plausible and otherwise attractive view of reality as tensed which, for reasons still inexplicable to us, has been almost entirely ignored in extant metaphysics of time (see Chisholm 1990 for one notable exception). Yet, after careful study of Kit Fine s massive paper Tense and Reality, to which we owe both insight and inspiration, we soon found ourselves embroiled in endless discussions about what the other views were with which our view was meant to contrast (Fine 2005: 261 320). It thus soon became clear that in order to show its merits, much more had to be done than merely to articulate this nonstandard A-theory and extract its consequences. We thus set ourselves the task of first getting all possible competitors into focus. This turned out to be a huge undertaking, which ultimately explains why what was originally conceived as a paper turned into a book. St Augustine famously complained that time proves elusive once the task is undertaken to give a philosophical account of what it is. A cursory look at the current literature on the philosophy of time suggests that not much has changed in this respect. Despite its conceptual sophistication and logical advances, contemporary philosophy would still seem to be at sea when it comes to the metaphysics of time. This is not to say that contemporary philosophers of time suffer from any indecision as to which sentences to affirm or reject. Quite the contrary, different patterns of assent and dissent can clearly be made out. Yet, these differences would often seem to betray a startling unclarity about what is at issue rather than express a disagreement about what is understood by all parties to be a single metaphysical doctrine. Many a discussion is obfuscated by inchoate pictures and tacit assumptions on either side about how to understand the debated claims and consequently about how to assess arguments for or against them. The best evidence for this intolerable state is provided by McTaggart s argument for the unreality of time. That some of the best philosophers of time have so widely disagreed on its proper formulation and assessment is itself a small-scale scandal. 1 1 See McTaggart 1908 and 1927. Whereas most follow Broad 1938 and Prior 1967 in regarding McTaggart s argument as fallacious, Mellor 1998 and, to some extent,
10 Preface Even if terms like tensed property, tensed fact or passage of time are good candidates for theory-laden terms, and so may acquire quite a different significance depending on the theory which embeds them, this can be no excuse. For, these terms can acquire such a different significance only if not all the terms do so. There should therefore be enunciable principles marking the contrasting ways in which these terms are being understood. However, such principles are hardly ever stated. And even when they are stated, debates about their relative merits are mostly perceived as being internal to the camp of those who take themselves to defend a realist view of tense. By contrast, proponents of anti-realism about tense, the B-theorists, would appear to have no stake in such debates, if only because they shirk the puzzling terms right from the start. But this appearance is deceptive. Arguments meant to count in favour of anti-realism cannot properly be gauged until it is settled whether they count against all available versions of realism. In this book, we aim to achieve more clarity and systematicity in this area than, to the best of our knowledge, has been achieved before. To this end, we give an exhaustive classification of mutually exclusive A-theories in terms of a set of precise criteria. Yet, as advertised in the beginning, we do not merely aim at a taxonomy of different realisms about tense, but also intend to explore a so far neglected A-theory that combines many of the virtues that the B-theory claims for itself, while avoiding many of the vices that afflict more standard A-theories. The plan for this book is as follows. In chapter 1, we offer an answer to the question of what the general distinction between A- and B-theories amounts to, contrasting this issue with the issue of what is involved in taking tense seriously. Thus we give a general formulation of what makes a theory an A-theory and what makes a theory a B-theory of time. In chapter 2, we then go on to specify desiderata that A-theories ought to fulfil, including minimal constraints on the conception of Dummett 1978 think that it is effective. But they do so for quite different reasons. This is no surprise as they give completely different reconstructions of the argument whose connections with the original remain obscure. Although Oaklander 2004 would seem to agree with Mellor, his reconstruction of McTaggart s argument, as well as his reasons for endorsing it, differ considerably from those suggested by Mellor. Lowe 1987 rejects both McTaggart s original argument and Dummett s reconstruction, but for reasons contrary to those given by Broad and Prior. Fine 2005 gives yet another version of the argument and suggests different ways of responding to it.
Preface 11 time s passage, or temporal change, as a real phenomenon, which will be fleshed out differently by different theories. Chapter 3 introduces the three key notions of constitution, truthmaking and fact-content, as well as definitions, axioms and derived principles involving them. Even if some of our definitions or axioms may, for all we know, be contested by some, their explicit formulation will at least ensure that qualms about the arguments we subsequently devise on their basis can be traced back to qualms about these definitions and axioms themselves. We thus aim to guarantee a high degree of argumentative perspicuousness and rigour. In chapter 4, we give precise criteria for distinguishing different versions of the A-theory which, modulo certain assumptions about the structure of time and the existence of facts, allow us to arrive at an exhaustive classification of mutually exclusive views. These criteria are both metaphysical and semantic in character. By their means, we identify a hitherto neglected family of views. Chapters 5 to 7 discuss three families of views, including Presentism and the non-standard view we aim to explore in more detail in the remainder of the book. In each case, we first show that to each of these views there corresponds a pre-theoretical picture of temporal reality which either influences philosophizing about time or at least has the potential to do so. Our characterisation of the respective views in terms of the proposed criteria can be seen as an attempt to give cognitive, non-pictorial content to these pictures, which is precisely what, according to a leading worker in the field, metaphysicians should do (Dummett 1991: 10). Subsequently, we discuss how these views fare in the light of the desiderata identified in chapter 2. In chapter 7, where we discuss our favourite A-theory, we show how this theory can escape the McTaggartian trilemma recently put forth by Fine (Fine 2005: 270 76). As it turns out, the mere availability of this view exposes Fine s argument as unsound. In chapter 8, we then devise a systematic metaphysics and semantics for a particular version of this non-standard A-theory which would seem to fare best in the light of the previously identified desiderata. In so doing, we give an account of the nature of tensed facts, offer a reduction of times, and of the temporal order, in terms of such facts and their properties and relations, and provide a full semantics, statable exclusively in tensed terms, for both the A- and the B-language. As it turns out, our preferred A-theory shares many nice features with the
12 Preface B-theory, and so arguments promoting these features can just as well be taken as arguments in its favour. Nevertheless our preferred view is a genuine A-theory and not just a B-theory in disguise. This will be shown in chapter 9 which brings our discussion to a close. Everyone has to start somewhere. There is no such thing as a philosophical account free of any presuppositions. Thus, we make certain assumptions about time and its structure that we will not subject to further discussion. First, we will ignore the impact that relativistic physics is commonly thought to have on the metaphysics of time. Arguably, certain prominent A-theories such as Presentism are at odds with relativistic physics, and hence would otherwise drop out of the picture. Moreover, there is some reason to believe that, at least as far as Special Relativity is concerned, our preferred A-theory can be extended so as to heed its results. Lastly, to the extent that it is as yet an open issue how relativistic physics might be reconciled with quantum mechanics, it would be premature to discard, from the onset, any metaphysical views that are in tension with the former. Secondly, we assume that the time-order is transitive, asymmetric and linear. We thereby exclude both cyclic time and branching time. Thirdly, we assume that time is measurable so that, given any two times, there is a certain number which measures their distance, given a previously chosen time-unit (e.g. that of a day). Besides these assumptions about time and its structure, we also assume that talk about facts in general and quantification over such facts in particular make good sense. We thereby exclude certain varieties of deflationism about fact-talk (Field 1994 and Horwich 1998). When discussing semantics, we furthermore assume the truth-conditional paradigm. We thereby exclude certain views that take some notion of assertibility distinct from truth to be the core concept of semantic theorizing (Dummett 1978, 1993 and 2004). Work on this book involved a lot of travelling back and forth between Geneva, where Fabrice presently holds a Swiss National Science Foundation Professorship (University of Geneva, project PP001-114758), and Barcelona, where Sven holds a Research Professorship at the Catalan Institute for Research and Advanced Studies (ICREA). It soon turned out that most of the work had to be done face to face, with telecommunication being a last resort, not only because we often felt the need to go through arguments with paper and pen, but also because
Preface 13 our sometimes rather different ways of thinking about philosophical issues required the opportunity of instant clarification. For a long time, we tried to publish some of the ideas put forth in this book in the form of articles. With one exception (Correia and Rosenkranz forthcoming), the experience has been rather frustrating. The majority of referee reports we received complained that our ways of conceiving the debate deviate from the standard and, oddly, declared this a chief reason for rejecting the submitted work. One would have thought that at least in academic philosophy a fresh look at well-worn problems would always be welcome. Not so. Fortunately, we both had ample opportunity to present, jointly or separately, earlier versions of the material contained in this book to expert audiences in Barcelona, Berlin, Geneva, Krakow and other places. Thanks to all who participated in discussion on those occasions and especially to those who took the pains to read through earlier, rather convoluted manuscripts. Special thanks go to Ofra Magidor, Elia Zardini, Kit Fine, Dean Zimmerman, Ghislain Guigon, Manuel García-Carpintero and Carl Hoefer who provided us with immensely valuable feedback that helped to significantly improve our arguments and to clarify our own ideas. We would also like to acknowledge that the research leading to these results has received funding from the European Community s Seventh Framework Programme under grant agreement PITN-GA-2009-238128, and was also partially funded by the Consolider-Ingenio project CSD2009-0056, the project FFI 2008-06153 and the project HUM2007-61108, all financed by the Spanish Ministry of Science and Innovation (MICINN), as well as by the project CRSI11-127488, financed by the Swiss National Science Foundation. Our final thanks go to Artur Serra Costa for the cover illustration and to Michael Kienecker from mentis for his support throughout the publication process.