Abstract

Comment: This translation contains a correction of an argument in the original English edition, a correction that was subsequently made in the 1999 English Paperback edition, The correction is described below in the final paragraph. Differences in language can seriously restrict one's access to, and knowledge of, the philosophical work that's being done in other countries, and before the publication in 1997 of my book Time, Tense, and Causation, I was not aware of the depth of interest, in Italy, in analytical philosophy in general, and metaphysics in particular. Since that time, however, I've had the opportunity of talking to, and corresponding with, Italian philosophers who are currently working very intensely on problems in the philosophy of time. I very much enjoyed those discussions, and so I'm very pleased indeed that my book has now been translated into Italian. The introduction to the book will provide readers with quite a detailed overview of my approach to the philosophy of time, and of the main theses that I am defending. But perhaps it will be helpful here if I try to sketch, very briefly, the big picture. The central issue in the philosophy of time concerns the choice between tensed and tenseless accounts of the nature of time – or, as I prefer to express it, between dynamic and static conceptions of reality. According to tensed (or dynamic) accounts, there are significant ontological differences between the past, the present, and the future – either because the world contains intrinsic tensed properties of passiveness, presentness, and futurity, or else because the past, the present, and the future are not all equally real. In contrast, according to tenseless (or static) views of the nature of time, there are no intrinsic tensed properties, and the past, the present, and the future are all equally real. In this book, I defend a dynamic view of time dash specifically, one according to which, while the past and the present are now real, the future is not. This view has, of course, a very long history, with a version of it having been defended by Aristotle in his famous discussion of the sea battle tomorrow, in which he argued that, although it is now true – indeed necessarily so – that either there will be a sea battle tomorrow or there will not be one, it is not now true that there will be a sea battle tomorrow, and not now true that there will not be one. Only when tomorrow comes will the world contain states of affairs that make one of these propositions true, and the other false. But while this general view of the nature of time has a very long and distinguished history – and also seems, intuitively, quite appealing – it has become clear, especially in this century, that it is exposed to very strong objections – objections moreover, that come not merely from philosophy, but also from contemporary physics, and especially from Einstein's special theory of relativity. One of the main challenges accordingly, for any defense of a tensed or dynamic view of time, is to show that those objections can be answered. In grappling with those objections, however, one thing that emerged very clearly was that some theses that defenders of tensed approaches to time have traditionally viewed as absolutely essential must be abandoned as unsound. The result is that. I was led to a view of the nature of time that is, in many respects, intermediate between tenseless views of time and traditional tensed approaches. In particular, advocates of traditional tensed views almost always maintain that the simplest temporal facts are themselves inherently tensed: they consist of facts such as, for example, that is certain apple is now red. But I maintain that, on the contrary, the simplest temporal facts, rather than being intrinsically tensed, are facts to the effect, for example, that a certain apple is now red at time t. On this fundamental issue, then, I agree with those who accept a tenseless or static view of time, since they too hold that the simplest tensed facts ¬– and indeed all tensed facts – are not tensed facts. How, then, does my approach to the nature time differ from a tenseless or static approach? The answer is that I also maintain that, although basic tensed facts are not inherently tensed, the world is nevertheless a dynamic one, since every present moment is a point at which things come into existence. Events, therefore, are not merely actual or nonactual – as is maintained by advocates of tenseless approaches to time. Rather an event is actual as of some time, and not actual as of other times. One needs, therefore, a temporally indexed notion of actuality, according to which an event is not actual until the time at which it occurs, and given that notion, one can explain, in a straightforward fashion, what it is for events to lie in the past, the present, and the future, and in the way that entails that the past and the present are real, but the future is not. One task, as I have said, is to show that the many objections that have been advanced against dynamic conceptions of the world dash by philosophers – such as McTaggart, Quine, Smart, Putnam, and Mellor – can be answered. But even if, as I claim, this can be done, one is still left, of course, with the question of what positive reason there is, if any, for accepting a tensed or dynamic view of the world. The argument that I develop in response to this question centers upon the concept of causation, and here I argue, first, that there are decisive objections to reductionist approaches to causation; secondly, that it is possible to set out a very plausible realistic account of the nature of causation; and, thirdly, that the crucial postulates that are involved in that account can only be satisfied in a dynamic world – indeed only in a dynamic world in which the past and the present are real, but the future is not. This way of defending the view that our world is a dynamic one also has implications for some other issues – in particular, issues connected with the subtle and very difficult metaphysical question of the relation between time and causation. Thus, after setting out the above argument, I attempt to show that if causation can exist only in a dynamic world, then one can both demonstrate that backward causation is logically impossible and defend the view that the direction of time is to be defined in terms of the direction of causation, rather than vice versa. Finally, a comment on the text. It involves one major change from the original English edition – namely in sections 4. 6.2 and 4.7. The change in those sections involves the crucial part in my argument both for the claim that our world is one where the past and present are real, but the future is not, and for the claim that backward causation is logically impossible. It was pointed out to me by Kenji Murota, a graduate student of philosophy at Keio University, that there was a problem in my original formulation of that argument. I'm grateful to him for his incisive criticism, and I'm pleased that I've had the opportunity of correcting that argument in the present edition.