A modest proposal concerning laws, counterfactuals, and explanations - - Why be Humean? -- Suggestions from physics for deep metaphysics -- On the passing of time -- Causation, counterfactuals, and the third factor -- The whole ball of wax -- Epilogue : a remark on the method of metaphysics.

As we navigate through life, we model time as flowing, the present as special, and the past as “dead.” This model of time—manifest time—develops in childhood and later thoroughly infiltrates our language, thought, and behavior. It is part of what makes a human life recognizably human. Yet if physics is correct, this model of the world is deeply mistaken. This book is about this conflict between manifest and physical time. The first half dives into the physics and philosophy to establish (...) the conflict’s existence; but it also argues that the claim that physics “spatializes” time is overstated. Rather, even relativity theory makes time special in deep and significant ways. The second half turns to psychology, biology, and more, seeking to understand why creatures like us develop manifest time. The novel picture that results is that manifest time is a natural reaction to the many cognitive and evolutionary challenges that we face. For subjects embedded in our circumstances, it makes sense to develop—even if fundamentally wrong. (shrink)

David Albert and Barry Loewer have argued that the temporal asymmetry of our concept of causal influence or control is grounded in the statistical mechanical assumption of a low-entropy past. In this paper I critically examine Albert's and Loewer 's accounts.

Huw Price has argued that on an interventionist account of cause the distinction is perspectival, and the claim prompted some interesting responses from interventionists and in particular an exchange with Woodward that raises questions about what it means to say that one or another structure is perspectival. I’ll introduce his reasons for claiming that the distinction between cause and effect on an interventionist account is perspectival. Then I’ll introduce a distinction between different ways in which a class of concepts can (...) be said to depend on facts about their users. Three importantly different forms of dependence will emerge from the discussion: Pragmatic dependence on us: truth conditions for x-beliefs can be given by a function f \ of more fundamental physical structures making no explicit reference to human agents. But there are any other number of functions ) ontologically on a par with x and what explains the distinguished role f plays in our practical and epistemic lives are facts about us. Implicit relativization: truth conditions for x-beliefs are relative to agent or context; the context supplies the value of a hidden parameter that determines the truth of x-beliefs. Indexicals: like implicit relativization except that the surface syntax contains a term whose semantic value is context-dependent. I suggest that Price’s insights are best understood in the first way. This will draw a crucial disanalogy with his central examples of perspectival concepts, but it will refine the thesis in a way that is more faithful to what his arguments show. The refined thesis will also support generalization to other concepts, and clarify the foundations of the quite distinctive research program that Price has been developing for a number of years. (shrink)

Concepts employed in folk descriptions of the world often turn out to be more perspectival than they seem at first sight, involving previously unrecognised sensitivity to the viewpoint or 'situation' of the user of the concept in question. Often, it is progress in science that reveals such perspectivity, and the deciding factor is that we realise that other creatures would apply the same concepts with different extension, in virtue of differences between their circumstances and ours. In this paper I argue (...) that causal concepts are perspectival in this way, and describe the 'situation' on which they depend in terms of an abstract characterisation of the viewpoint of a deliberating agent. I argue that this approach makes better sense than rivals of the apparent asymmetry and temporal orientation of the causal relation. (shrink)

This book is an attempt to get to the bottom of an acute and perennial tension between our best scientific pictures of the fundamental physical structure of the world and our everyday empirical experience of it. The trouble is about the direction of time. The situation (very briefly) is that it is a consequence of almost every one of those fundamental scientific pictures--and that it is at the same time radically at odds with our common sense--that whatever can happen can (...) just as naturally happen backwards. Albert provides an unprecedentedly clear, lively, and systematic new account--in the context of a Newtonian-Mechanical picture of the world--of the ultimate origins of the statistical regularities we see around us, of the temporal irreversibility of the Second Law of Thermodynamics, of the asymmetries in our epistemic access to the past and the future, and of our conviction that by acting now we can affect the future but not the past. Then, in the final section of the book, he generalizes the Newtonian picture to the quantum-mechanical case and (most interestingly) suggests a very deep potential connection between the problem of the direction of time and the quantum-mechanical measurement problem. The book aims to be both an original contribution to the present scientific and philosophical understanding of these matters at the most advanced level, and something in the nature of an elementary textbook on the subject accessible to interested high-school students. Table of Contents: Preface 1. Time-Reversal Invariance 2. Thermodynamics 3. Statistical Mechanics 4. The Reversibility Objections and the Past-Hypothesis 5. The Scope of Thermodynamics 6. The Asymmetries of Knowledge and Intervention 7. Quantum Mechanics Appendix: Gedankenexperiments with Heat Engines Index Reviews of this book: The foundations of statistical mechanisms are often presented in physics textbooks in a rather obscure and confused way. By challenging common ways of thinking about this subject, Time and Chance can do quite a lot to improve this situation. --Jean Bricmont, Science Albert is perfecting a style of foundational analysis that is uniquely his own...It has a surgical precision...and it is ruthless with pretensions. The foundations of thermodynamics is a topic that has accumulated a good deal of dead wood; this is a fire that will burn and burn. --Simon W. Saunders, Oxford University As usual with Albert's work, the exposition is brisk and to the point, and exceptionally clear...The book will be an extremely valuable contribution to the literature on the subject of philosophical issues in thermodynamics and statistical mechanics, a literature which has been thin on the ground but is now growing as it deserves to. --Lawrence Sklar, University of Michigan. (shrink)

This article deals with the question of what time reversal means. It begins with a presentation of the standard account of time reversal, with plenty of examples, followed by a popular non-standard account. I argue that, in spite of recent commentary to the contrary, the standard approach to the meaning of time reversal is the only one that is philosophically and physically viable. The article concludes with a few open research problems about time reversal.

The final work of a distinguished physicist, this remarkable volume examines the emotive significance of time, the time order of mechanics, the time direction of thermodynamics and microstatistics, the time direction of macrostatistics, and the time of quantum physics. Coherent discussions include accounts of analytic methods of scientific philosophy in the investigation of probability, quantum mechanics, the theory of relativity, and causality. "[Reichenbach’s] best by a good deal."—Physics Today. 1971 ed.

Author Max Black argues that language should conform to the discovered regularities of experience it is radically mistaken to assume that the conception of language is a mirror of reality.

Author Max Black argues that language should conform to the discovered regularities of experience it is radically mistaken to assume that the conception of language is a mirror of reality.

Time is woven into the fabric of our lives. Everything we do, we do in and across time. It is not just that our lives are stretched out in time, from the moment of birth to the moment of our death. It is that our lives are stories. We make sense of ourselves, today, by understanding who we were yesterday, and the day before, and the day before that; by understanding what we did and why we did it. Our memories (...) shape our present selves, since we are the product of who we were, and who we remember being. Yet who we are lasts for but a moment. It is who we will be that demands attention. We are forever projecting ourselves into the future. We painstakingly plan for the needs of our future selves, all the while knowing that while what we do will make those future selves who they are, still, our future selves are elusive. So it is not simply that we happen to live our lives in time, the way, say, one might happen to live in Australia, or Singapore. It is hard to fathom how things could be otherwise. What would it be to live a life without time? Yet time itself is intangible. Though we are keenly aware of what has been ‒ of pain and loss, regret and pride ‒ and of what might be ‒ of anticipation, and dread, and longing ‒ time itself seems unaffected by anything we do. Though we can anticipate a future birthday cake, time itself cannot be tasted. Though we can dread a future dentist’s appointment, time itself cannot be touched. Though we remember the crunching of leaves this past autumn, time itself cannot be heard. How can it be that something so central to each of us, to who we are, and what we care about, can be so spectral? What, in the end, is time? Is time real, like a substance in which each of us, like insects in amber, finds ourselves trapped? Is time a dimension through which we can move? Is time not a thing at all, but some connection between events? If time is real, what is it like? Does it flow like a river, taking each of us prisoner in its current, washing us ever closer to the end of our lives? Is time like a cresting wave, coming ever closer to each of us from the future, engulfing us, and then receding into the past? Or is time static? Like a one-way road that each of us might wander, with no chance to turn back? Or perhaps time is like none of these things. Perhaps time is more like space; something we can navigate freely, so that we can visit different times just like we visit different places. Perhaps we can we travel in time the way we can travel in space. These questions, and many more, are the focus of this book. Now, you might wonder what philosophers are doing writing a book about time. Surely that’s a job for physicists! It is true: a great deal of what we know about time stems from our understanding of physics. However, even in physics we find that there are questions about time that go unanswered. Moreover, increasingly, physicists are turning to philosophers for help in understanding the role that time plays in current physical theories. Our goal is to get the reader up to speed on some of the central issues that influence our understanding of time so that they too may play a role in this ongoing discussion between science and philosophy. We hope that in doing so it will become clear what philosophy can bring to the study of time. There is a natural narrative in philosophy regarding the study of time, and we have chosen to organise this book according to that narrative. However, the book may also be approached in a ‘choose-your-own adventure’ spirit. While later chapters build on material introduced in earlier chapters, you can skip around, reading the book in any order you choose. For the instructor, this means that she can design her course around this book in any number of ways, depending on the particular topic she wishes to focus on. (shrink)

The paper has two parts: First, I describe a relatively popular thesis in the philosophy of propositional attitudes, worthy of the name ‘taking tense seriously’; and I distinguish it from a family of views in the metaphysics of time, namely, the A-theories (or what are sometimes called ‘tensed theories of time’). Once the distinction is in focus, a skeptical worry arises. Some A-theorists maintain that the difference between past, present, and future, is to be drawn in terms of what exists: (...) growing-block theorists eschew ontological commitment to future entities; presentists, to future and past entities. Others think of themselves as A-theorists but exclude no past or future things from their ontology. The metaphysical skeptic suspects that their attempt to articulate an ‘eternalist’ version of the A-theory collapses into merely ‘taking tense seriously’– a thesis that does not imply the A-theory. The second half of the paper is the search for a stable eternalist A-theory. It includes discussion of temporary intrinsics, temporal parts, and truth. (shrink)

A time-symmetric formulation of nonrelativistic quantum mechanics is developed by applying two consecutive boundary conditions onto solutions of a time- symmetrized wave equation. From known probabilities in ordinary quantum mechanics, a time-symmetric parameter P0 is then derived that properly weights the likelihood of any complete sequence of measurement outcomes on a quantum system. The results appear to match standard quantum mechanics, but do so without requiring a time-asymmetric collapse of the wavefunction upon measurement, thereby realigning quantum mechanics with an important (...) fundamental symmetry. (shrink)

The aim of this article is to analyse the relation between the second law of thermodynamics and the so-called arrow of time. For this purpose, a number of different aspects in this arrow of time are distinguished, in particular those of time-reversal (non-)invariance and of (ir)reversibility. Next I review versions of the second law in the work of Carnot, Clausius, Kelvin, Planck, Gibbs, Caratheodory and Lieb and Yngvason, and investigate their connection with these aspects of the arrow of time. It (...) is shown that this connection varies a great deal along with these formulations of the second law. According to the famous formulation by Planck, the second law expresses the irreversibility of natural processes. But in many other formulations irreversibility or even time-reversal non-invariance plays no role. I therefore argue for the view that the second law has nothing to do with the arrow of time. (shrink)

The aim of this paper is to construct a version of Bohm’s model that also includes the existence of backwards-in-time influences in addition to the usual forwards causation. The motivation for this extension is to remove the need in the existing model for a preferred reference frame. As is well known, Bohm’s explanation for the nonlocality of Bell’s theorem necessarily involves instantaneous changes being produced at space-like separations, in conflict with the “spirit” of special relativity even though these changes are (...) not directly observable. While this mechanism is quite adequate from a purely empirical perspective, the overwhelming experimental success of special relativity (together with the theory’s natural attractiveness), makes one reluctant to abandon it even at a “hidden” level. There are, of course, trade-offs to be made in formulating an alternative model and it is ultimately a matter of taste as to which is preferred. However, constructing an explicit example of a causally symmetric formalism allows the pros and cons of each version to be compared and highlights the consequences of imposing such symmetry. In particular, in addition to providing a natural explanation for Bell nonlocality, the new model allows us to define and work with a mathematical description in 3-dimensional space, rather than configuration space, even in the correlated many-particle case. (shrink)

A system whose expected state changes with time cannot have both a forward-directed translationally invariant probabilistic law and a backward-directed translationally invariant law. When faced with this choice, science seems to favor the former. An asymmetry between cause and effect may help to explain why temporally oriented laws are usually forward-directed.

We articulate the problems posed by the quantum liar experiment (QLE) for backwards causation interpretations of quantum mechanics, time-symmetric accounts and other dynamically oriented local hidden variable theories. We show that such accounts cannot save locality in the case of QLE merely by giving up “lambda-independence.” In contrast, we show that QLE poses no problems for our acausal Relational Blockworld interpretation of quantum mechanics, which invokes instead adynamical global constraints to explain Einstein–Podolsky–Rosen (EPR) correlations and QLE. We make the case (...) that the acausal and adynamical perspective is more fundamental and that dynamical entities obeying dynamical laws are emergent features grounded therein. (shrink)

This paper is a tour of how the laws of nature can distinguish between the past and the future, or be T-violating. I argue that, in terms of the basic argumentative structure, there are basically just three approaches currently being explored. The first is an application of Curie's Principle, together with the CPT theorem. The second route makes use of a principle due to Pasha Kabir which allows for a direct detection. The third route makes use of a Non-degeneracy Principle, (...) and is related to the energy spectrum of elementary particles. I show how each provides a general template for detecting T-violation, illustrate each with an example, and discuss their prospects in extensions of particle physics beyond the standard model. (shrink)

The nature of experience has been held to be a major reason for accepting the A-theory of time. I argue, however, that experience does not favour the A-theory over the B-theory; and that even if the A-theory were true it would not be possible to perceive the passage of time. The main argument for this draws on the constraint that a satisfactory theory of perception must explain why phenomenal characters map uniquely onto perceived worldly features. Thus, if passage is perceived, (...) it must be explained what makes one phenomenal character rather than another a perception of passage; and it must also be explained why that phenomenal character is a perception of passage rather than of some other feature of the world. I argue that no such explanation can be given, and consequently that passage cannot be perceived. I conclude that the A-theory is rendered unintelligible, and should therefore be rejected. (shrink)

Physics takes for granted that interacting physical systems with no common history are independent, before their interaction. This principle is time-asymmetric, for no such restriction applies to systems with no common future, after an interaction. The time-asymmetry is normally attributed to boundary conditions. I argue that there are two distinct independence principles of this kind at work in contemporary physics, one of which cannot be attributed to boundary conditions, and therefore conflicts with the assumed T (or CPT) symmetry of microphysics. (...) I note that this may have interesting ramifications in quantum mechanics. (shrink)

It has often been suggested that retrocausality offers a solution to some of the puzzles of quantum mechanics: e.g., that it allows a Lorentz-invariant explanation of Bell correlations, and other manifestations of quantum nonlocality, without action-at-a-distance. Some writers have argued that time-symmetry counts in favour of such a view, in the sense that retrocausality would be a natural consequence of a truly time-symmetric theory of the quantum world. Critics object that there is complete time-symmetry in classical physics, and yet no (...) apparent retrocausality. Why should the quantum world be any different? This note throws some new light on these matters. I call attention to a respect in which quantum mechanics is different, under some assumptions about quantum ontology. Under these assumptions, the combination of time-symmetry without retrocausality is unavailable in quantum mechanics, for reasons intimately connected with the differences between classical and quantum physics (especially the role of discreteness in the latter). Not all interpretations of quantum mechanics share these assumptions, however, and in those that do not, time-symmetry does not entail retrocausality. (shrink)

Since the late nineteenth century, physics has been puzzled by the time-asymmetry of thermodynamic phenomena in the light of the apparent T-symmetry of the underlying laws of mechanics. However, a compelling solution to this puzzle has proved elusive. In part, I argue, this can be attributed to a failure to distinguish two conceptions of the problem. According to one, the main focus of our attention is a time-asymmetric lawlike generalisation. According to the other, it is a particular fact about the (...) early universe. This paper aims (i) to distinguish these two different conceptions of the time-asymmetric explanandum in thermodynamics; (ii) to argue in favour of the latter; and (iii) to show that whichever we choose, our rational expectations about the thermodynamic behaviour of the future must depend on what we know about the past: contrary to the common view, statistical arguments alone do not give us good reason to expect that entropy will always continue to increase. (shrink)

Huw Price argues that there are two conceptions of the puzzle of the time‐asymmetry of thermodynamics. He thinks this puzzle has remained unsolved for so long partly due to a misunderstanding about which of these conceptions is the right one and what form a solution ought to take. I argue that it is Price's understanding of the problem which is mistaken. Further, it is on the basis of this and other misunderstandings that he disparages a type of account which does, (...) in fact, hold promise of a solution. (shrink)

In a recent paper, Malament (2004) employs a time reversal transformation that differs from the standard one, without explicitly arguing for it. This is a new and important understanding of time reversal that deserves arguing for in its own right. I argue that it improves upon the standard one. Recent discussion has focused on whether velocities should undergo a time reversal operation. I address a prior question: What is the proper notion of time reversal? This is important, for it will (...) affect our conclusion as to whether our best theories are time-reversal symmetric, and hence whether our spacetime is temporally oriented. *Received February 2007; revised March 2008. †To contact the author, please write to: Department of Philosophy, Yale University, P.O. Box 208306, New Haven, CT 06520-8306; e-mail: [email protected]. (shrink)

Mathias Frisch has argued that the requirement that electromagnetic dispersion processes are causal adds empirical content not found in electrodynamic theory. I urge that this attempt to reconstitute a local principle of causality in physics fails. An independent principle is not needed to recover the results of dispersion theory. The use of ‘causality conditions’ proves to be the mere adding of causal labels to an already presumed fact. If instead one seeks a broader, independently formulated grounding for the conditions, that (...) grounding either fails or dissolves into vagueness and ambiguity, as has traditionally been the fate of candidate principles of causality. Introduction Scattering in Classical Electrodynamics Sufficiency of the Physics Failure of the Principle of Causality Proposed 4.1 A sometimes principle 4.2 The conditions of applicability are obscure 4.3 Effects can come before their causes 4.4 Vagueness of the relata and of the notion of causal process Conclusion CiteULike Connotea Del.icio.us What's this? (shrink)

Mathias Frisch has argued that the requirement that electromagnetic dispersion processes are causal adds empirical content not found in electrodynamic theory. I urge that this attempt to reconstitute a local principle of causality in physics fails. An independent principle is not needed to recover the results of dispersion theory. The use of ‘causality conditions’ proves to be the mere adding of causal labels to an already presumed fact. If instead one seeks a broader, independently formulated grounding for the conditions, that (...) grounding either fails or dissolves into vagueness and ambiguity, as has traditionally been the fate of candidate principles of causality. 1. Introduction2. Scattering in Classical Electrodynamics3. Sufficiency of the Physics4. Failure of the Principle of Causality Proposed 4.1. A sometimes principle4.2. The conditions of applicability are obscure4.3. Effects can come before their causes4.4. Vagueness of the relata and of the notion of causal process5. Conclusion. (shrink)

This paper examines the relationship between physical theories of causation and theories of difference-making. It is plausible to think that such theories are compatible with one another as they are aimed at different targets: the former, an empirical account of actual causal relations; the latter, an account that will capture the truth of most of our ordinary causal claims. The question then becomes: what is the relationship between physical causation and difference-making? Is one kind of causal fact more fundamental than (...) the other? This paper defends causal foundationalism: the view that facts about difference-making are dependent on the obtaining of facts about physical causation. However, the paper's main goal is to clarify the structure of the debate. At the end of the paper, it is shown how settling the issue about the relationship between physical theories of causation and theories of difference-making has more than mere intrinsic interest in unifying the very different pursuits that have been undertaken in the philosophy of causation. It can help to break a stalemate that has arisen in the current debate about mental causation. (shrink)

This essay is the first act of a two-act play. My ultimate aim is to defend a simple proposition: time passes. To be more precise, I want to defend the claim that the passage of time is an intrinsic asymmetry in the structure of space-time itself, an asymmetry that has no spatial counterpart and is metaphysically independent of the material contents of space-time. It is independent, for example, of the entropy gradient of the universe. This view is part of common-sense, (...) but has been widely attacked by philosophers. The passage of time, we are told, is a myth, an illusion, even an incoherent notion. Because the notion that time passes is common sense, it perhaps requires little positive defence; if there are no weighty objections to the view, it ought to be accepted. So the first, and more important, act of the play is defusing the arguments which have been used to cast doubt on the passage of time. I have positive arguments to give, but not having space for them here, I will confine myself to an examination of the common philosophical arguments that have been used to cast doubt on the passage of time. (shrink)

Albert provides a sketch of an entropy account of the causal and counterfactual asymmetries. This paper critically examines a proposal that may be thought to fill in some of the lacunae in Albert’s account.

David Albert claims that classical electromagnetic theory is not time reversal invariant. He acknowledges that all physics books say that it is, but claims they are ``simply wrong" because they rely on an incorrect account of how the time reversal operator acts on magnetic fields. On that account, electric fields are left intact by the operator, but magnetic fields are inverted. Albert sees no reason for the asymmetric treatment, and insists that neither field should be inverted. I argue, to the (...) contrary, that the inversion of magnetic fields makes good sense and is, in fact, forced by elementary geometric considerations. I also suggest a way of thinking about the time reversal invariance of classical electromagnetic theory -- one that makes use of the invariant (four-dimensional) formulation of the theory -- that makes no reference to magnetic fields at all. It is my hope that it will be of interest in its own right, Albert aside. It has the advantage that it allows for arbitrary curvature in the background spacetime structure, and is therefore suitable for the framework of general relativity. (The only assumption one needs is temporal orientability.). (shrink)

Among the most important questions in the metaphysics of science are "What are the natures of fundamental laws and chances?" and "What grounds the direction of time?" My aim in this paper is to examine some connections between these questions, discuss two approaches to answering them and argue in favor of one. Along the way I will raise and comment on a number of issues concerning the relationship between physics and metaphysics and consequences for the subject matter and methodology of (...) metaphysics. (shrink)

The distribution of matter in our universe is strikingly time asymmetric. Most famously, the Second Law of Thermodynamics says that entropy tends to increase toward the future but not toward the past. But what explains this time-asymmetric distribution of matter? In this paper, I explore the idea that time itself has a direction by drawing from recent work on grounding and metaphysical fundamentality. I will argue that positing such a direction of time, in addition to time-asymmetric boundary conditions, enables a (...) better explanation of the thermodynamic asymmetry than is available otherwise. (shrink)

Is time flowing? A-theorists say yes, B-theorists say no. But both take time to be real. It means that B-theorists accept that time might be real, even if lacking a property usually ascribed to it. In this paper, I want to ask what are the different properties usually ascribed to time in order to draw the list of different possible kinds of realism and anti-realism about time. As we will see, there are three main kinds of anti-realism. I will claim (...) that if time is defined as the universe’s fourth dimension, there is no way time could be unreal. (shrink)

I assess the thesis that counterfactual asymmetries are explained by an asymmetry of the global entropy at the temporal boundaries of the universe, by developing a method of evaluating counterfactuals that includes, as a background assumption, the low entropy of the early universe. The resulting theory attempts to vindicate the common practice of holding the past mostly fixed under counterfactual supposition while at the same time allowing the counterfactual's antecedent to obtain by a natural physical development. Although the theory has (...) some success in evaluating a wide variety of ordinary counterfactuals, it fails as an explanation of counterfactual asymmetry. (shrink)