Quantum mechanics seems to portray nature as nonseparable, in the sense that it allows spatiotemporally separated entities to have states that cannot be fully specified without reference to each other. This is often said to implicate some form of “holism.” We aim to clarify what this means, and why this seems plausible. Our core idea is that the best explanation for nonseparability is a “common ground” explanation, which casts nonseparable entities in a holistic light, as scattered reflections of a more (...) unified underlying reality. (shrink)

In 1687 Isaac Newton ushered in a new scientific era in which laws of nature could be used to predict the movements of matter with almost perfect precision. Newton's physics also posed a profound challenge to our self-understanding, however, for the very same laws that keep airplanes in the air and rivers flowing downhill tell us that it is in principle possible to predict what each of us will do every second of our entire lives, given the early conditions of (...) the universe. Can it really be that even while you toss and turn late at night in the throes of an important decision and it seems like the scales of fate hang in the balance, that your decision is a foregone conclusion? Can it really be that everything you have done and everything you ever will do is determined by facts that were in place long before you were born? This problem is one of the staples of philosophical discussion. It is discussed by everyone from freshman in their first philosophy class, to theoretical physicists in bars after conferences. And yet there is no topic that remains more unsettling, and less well understood. If you want to get behind the façade, past the bare statement of determinism, and really try to understand what physics is telling us in its own terms, read this book. The problem of free will raises all kinds of questions. What does it mean to make a decision, and what does it mean to say that our actions are determined? What are laws of nature? What are causes? What sorts of things are we, when viewed through the lenses of physics, and how do we fit into the natural order? Ismael provides a deeply informed account of what physics tells us about ourselves. The result is a vision that is abstract, alien, illuminating, and-Ismael argues-affirmative of most of what we all believe about our own freedom. Written in a jargon-free style, How Physics Makes Us Free provides an accessible and innovative take on a central question of human existence. (shrink)

Quantum mechanics seems to portray nature as nonseparable, in the sense that it allows spatiotemporally separated entities to have states that cannot be fully specified without reference to each other. This is often said to implicate some form of “holism.” We aim to clarify what this means, and why this seems plausible. Our core idea is that the best explanation for nonseparability is a “common ground” explanation, which casts nonseparable entities in a holistic light, as scattered reflections of a more (...) unified underlying reality. (shrink)

J. T. Ismael's monograph is an ambitious contribution to metaphysics and the philosophy of language and mind. She tackles a philosophical question whose origin goes back to Descartes: What am I? The self is not a mere thing among things--but if so, what is it, and what is its relationship to the world? Ismael is an original and creative thinker who tries to understand our problematic concepts about the self and how they are related to our use of language in (...) particular. (shrink)

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)

First para: Before the 17th century, there was not much discussion, and little uniformity in conception, of natural laws. The rise of science in 17th century, Newton’s mathematization of physics, and the provision of strict, deterministic laws that applied equally to the heavens and to the terrestrial realm had a profound impact in transforming the philosophical imagination. A philosophical conception of physical law built on the example of Newtonian Mechanics became quickly entrenched. Between the 17th and 20th centuries, there was (...) a great deal of philosophical interest in probabilities, but probabilities were mostly regarded as having something to do with the management of opinion, not as having a fundamental role in science. Probabilities made their first appearance in an evidently ineliminable way in the laws of a fundamental theory with the advent of quantum mechanics. Quantum probabilities have come to be called ‘chances’ in the philosophical literature, and their interpretation has been one of the central problems in philosophy of science now for almost a century. There continue to be hold-outs that insist that there must be an underlying probability-free replacement for quantum mechanics and Bohmians have had some success in formulating a deterministic alternative to quantum mechanics, but most physicists accept that the probabilistic character of the quantum mechanical laws is likely to be retained in any successor theory. While physics has adjusted itself comfortably to the existence of ineliminably probabilistic laws, philosophy has not managed arrive at a stable interpretation of quantum probability. The difficulty is that there are a number of constraints that an interpretation of chance must satisfy, constraints that appear to be partially definitive of the concept and it proves to be extraordinarily difficult to meet them simultaneously. (shrink)

Before the twentieth century, the Universe was usually imagined as a large spatially extended thing unfolding in time. The past was fixed and the future was open; unfolding was conceived as an asymmetric process of coming into being. Relativity introduced a new vision in which space and time are presented together as a single four-dimensional manifold of events. That, together with the fact that the fundamental laws of our classical theories are symmetric in time, made understanding why the past and (...) future present themselves so differently in our experience one of the central challenges of physics. The last two centuries have seen a great deal of progress in understanding various of the so-called arrows of time: the thermodynamic arrow, the cosmological arrow, the arrow of knowledge or information. There remains an outstanding piece of this puzzle that has seen little progress, one that Roger Penrose described in his beautiful paper Singularities and Time-Asymmetry in 1979 as: “The arrow most difficult to comprehend … namely the feeling of relentless forward temporal progression, according to which potentialities seem to be transformed into actualities.”I will propose that the insight needed to resolve the problem involves taking into account that we are part of the universe and that any attempt to model it as a totality involves self-reference. I will argue specifically that self-reference, against the background of a thermodynamic gradient, creates an instability in an embedded agent’s ability to know the future or even treat it as a potential object of knowledge. That instability captures the sense in which the future remains for her perpetually open and the passage of time resolves openness into the fixity of fact. (shrink)

In a famous passage drawing implications from determinism, Laplace introduced the image an intelligence who knew the positions and momenta of all of the particles of which the universe is composed, and asserted that in a deterministic universe such an intelligence would be able to predict everything that happens over its entire history. It is not, however, difficult to establish the physical possibility of a counterpredictive device, i.e., a device designed to act counter to any revealed prediction of its behavior. (...) What would happen if a Laplacean intelligence were put into communication with such a device and forced to reveal its prediction of what the device would do on some occasion? On the one hand, it seems that the Laplacean Intelligence should be able to predict the device's behavior. On the other hand, it seems like that device should be able to act counter to the prediction. An examination of the puzzle leads to clarification of what determinism does entail, with some insights about various other things along the way. (shrink)

In this paper, I defend an empiricist account of modality that keeps a substantive account of modal commitment, but throws out the metaphysics. I suggest that if we pair a deflationary attitude toward representation with a substantive account of how scientific models are constructed and put to use, the result is an account that deflates the metaphysics of modal commitment without deflating the content of modal claims.

This chapter addresses the worry that the existence of causal antecedents to your choices means that you are causally compelled to act as you do. It begins with the folk notion of cause, leads the reader through recent developments in the scientific understanding of causal concepts, and argues that those developments undermine the threat from causal antecedents. The discussion is then used as a model for a kind of naturalistic metaphysics that takes its lead from science, letting everyday concepts be (...) shaped and transformed by scientific developments. (shrink)

:Rawls ignited a debate in political theory when he introduced a division between the ideal and nonideal parts of a theory of justice. In the ideal part of the theory, one presents a positive conception of justice in a setting that assumes perfect compliance with the rules of justice. In the nonideal part, one addresses the question of what happens under departures from compliance. Critics of Rawls have attacked his focus on ideal theory as a form of utopianism, and have (...) argued that political theory should be focused instead on providing solutions to the manifest injustices of the real world. In this essay, I offer a defense of the ideal/nonideal theory distinction according to which it amounts to nothing more than a division of labor, and explore some scientific analogies. Rawls’s own focus on the ideal part of the theory, I argue, stems from a felt need to clarify the foundations of justice, rather than a utopian neglect of real world problems. (shrink)

Quantum mechanics is, at least at first glance and at least in part, a mathematical machine for predicting the behaviors of microscopic particles — or, at least, of the measuring instruments we use to explore those behaviors — and in that capacity, it is spectacularly successful: in terms of power and precision, head and shoulders above any theory we have ever had. Mathematically, the theory is well understood; we know what its parts are, how they are put together, and why, (...) in the mechanical sense (i.e., in a sense that can be answered by describing the internal grinding of gear against gear), the whole thing performs the way it does, how the information that gets fed in at one end is converted into what comes out the other. The question of what kind of a world it describes, however, is controversial; there is very little agreement, among physicists and among philosophers, about what the world is like according to quantum mechanics. Minimally interpreted, the theory describes a set of facts about the way the microscopic world impinges on the macroscopic one, how it affects our measuring instruments, described in everyday language or the language of classical mechanics. Disagreement centers on the question of what a microscopic world, which affects our apparatuses in the prescribed manner, is, or even could be, like intrinsically ; or how those apparatuses could themselves be built out of microscopic parts of the sort the theory describes.[1.. (shrink)

The chance of a physical event is the objective, single-case probability that it will occur. In probabilistic physical theories like quantum mechanics, the chances of physical events play the formal role that the values of physical quantities play in classical (deterministic) physics, and there is a temptation to regard them on the model of the latter as describing intrinsic properties of the systems to which they are assigned. I argue that this understanding of chances in quantum mechanics, despite being a (...) part of the orthodox interpretation of the theory and the most prevalent view in the physical community, is incompatible with a very wide range of metaphysical views about the nature of chance. The options that remain are unlikely to be attractive to scientists and scientifically minded philosophers. (shrink)

Is there more that one "Curie's principle"? How far are different formulations legitimate? What are the aspects that make it so scientifically fruitful, independently of how it is formulated? The paper is devoted to exploring these questions. We start with illustrating Curie's original 1894 article and his focus. Then, we consider the way that the discussion of the principle took shape from early commentators to its modern form. We say why we think that the modern focus on the inter-state version (...) of the principle loses sight of some of the most interesting significant applications of the principle. Finally, we address criticism of the principle put forward by Norton and purported counterexamples due to Roberts. (shrink)

The most potentially powerful objection to the possibility oftime travel stems from the fact that it can, under the right conditions, give rise to closedcausal loops, and closed causal loops can be turned into self-defeating causal chains;folks killing their infant selves, setting out to destroy the world before they were born,and the like. It used to be thought that such chains present paradoxes; the receivedwisdom nowadays is that they give rise to physical anomalies in the form of inexplicably correlated events. (...) I argue against the received wisdom. I can find nothing in them that argues against the possibility (even, the probability) of time travel. (shrink)

A reading is given of Curie''s Principle that the symmetry of a cause is always preserved its effects. The truth of the principle is demonstrated and its importance, under the proposed reading, is defended.As far as I see, all a priori statements in physics have their origin in symmetry. (Weyl, Symmetry, p. 126).

I propose, in the context of Everett interpretations of quantum mechanics, a way of understanding how there can be genuine uncertainty about the future notwithstanding that the universe is governed by known, deterministic dynamical laws, and notwithstanding that there is no ignorance about initial conditions, nor anything in the universe whose evolution is not itself governed by the known dynamical laws. The proposal allows us to draw some lessons about the relationship between chance and determinism, and to dispel one source (...) of the tendency among Everettians to introduce consciousness as a primitive element into physical description. (shrink)

The Hard Problem of the mind is addressed and it is argued that physical-phenomenal property identities have the same status as the identification of an ostended bit of physical space and the coordinates assigned the spot on a map of the terrain. It is argued, that is to say, that such identities are, or follow from, stipulations which interpret the map.

The chance of a physical event is the objective, single-case probability that it will occur. In probabilistic physical theories like quantum mechanics, the chances of physical events play the formal role that the values of physical quantities play in classical physics, and there is a temptation to regard them on the model of the latter as describing intrinsic properties of the systems to which they are assigned. I argue that this understanding of chances in quantum mechanics, despite being a part (...) of the orthodox interpretation of the theory and the most prevalent view in the physical community, is incompatible with a very wide range of metaphysical views about the nature of chance. The options that remain are unlikely to be attractive to scientists and scientifically minded philosophers. (shrink)

I want to consider some features of the position put forward by Julian Barbour in The End of Time that seem to me of particular philosophical interest. At the level of generality at which I'll be concerned with it, the view is relatively easy to describe. It can be arrived at by thinking of time as decomposing in some natural way linearly ordered atomic parts, ‘moments’, and combining an observation about the internal structure of moments with an epistemological doctrine about (...) our access to the past. The epistemological doctrine, which I'll call ‘Presentism’, following Butterfield, is the view that our access to the past is mediated by records, or local representations, of it. The observation is that the state of the world at any moment has the structure of what Barbour calls a ‘time capsule’, which is to say that it constitutes a partial record of its past, it is pregnant with interrelated mutually consistent representations of its own history. (shrink)

The intuitive notion of cause carries with it the idea of compulsion. When we learn that the dynamical laws are deterministic, we give this a causal reading and imagine our actions compelled to occur by conditions laid down at the beginning of the universe. Hume famously argued that this idea of compulsion is borrowed from experience and illegitimately projected onto regularities in the world. Exploiting the interventionist analysis of causal relations, together with an insight about the degeneracy of one’s epistemic (...) relations to one’s own actions, I defend a Humean position with regard to the idea of causal compulsion. Although I discuss only compulsion, a similar story could be told about the temporal directedness of causation. (shrink)

There’s a long history of discussion of probability in philosophy, but objective chance separated itself off and came into its own as a topic with the advent of a physical theory - quantum mechanics - in which chances play a central, and apparently ineliminable, role. In 1980 David Lewis wrote a paper pointing out that a very broad class of accounts of the nature of chance apparently lead to a contradiction when combined with a principle that expresses the role of (...) chance in guiding belief. There is still no settled agreement on the proper response to the Lewis problem. At the time he wrote the article, Lewis despaired of a solution, but, although he never achieved one that satisfied him completely, by 1994, due to work primarily by Thau and Hall, he had come to think the problem could be disarmed if we fudged a little on the meaning of ‘chance’. I’ll say more about this below. What I’m going to suggest, however, is that the qualification is unnecessary. The problem depends on an assumption that should be rejected, viz., that using information about chance to guide credence requires one to conditionalize on the theory of chance that one is using. I’m going to propose a general recipe for using information about chance to guide belief that does not require conditionalization on a theory of chance at any stage. Lewis’ problem doesn’t arise in this setting. (shrink)

Human beings think of themselves in terms of a privileged non-descriptive designator — a mental “I”. Such thoughts are called “_de se_” thoughts. The mind/body problem is the problem of deciding what kind of thing I am, and it can be regarded as arising from the fact that we think of ourselves non-descriptively. Why do we think of ourselves in this way? We investigate the functional role of “I” (and also “here” and “now”) in cognition, arguing that the use of (...) such non-descriptive “reflexive” designators is essential for making sophisticated cognition work in a general-purpose cognitive agent. If we were to build a robot capable of similar cognitive tasks as humans, it would have to be equipped with such designators. (shrink)

Dennett argues that the decentralized view of human cognitive organization finding increasing support in parts of cognitive science undermines talk of an inner self. On his view, the causal underpinnings of behavior are distributed across a collection of autonomous subsystems operating without any centralized supervision. Selves are fictions contrived to simplify description and facilitate prediction of behavior with no real correlate inside the mind. Dennett often uses an analogy with termite colonies whose behavior looks organized and purposeful to the external (...) eye, but which is actually the emergent product of uncoordinated activity of separate components marching to the beat of their individual drums. I examine the cognitive organization of a system steering by an internal model of self and environment, and argue that it provides a model that lies between the image of mind as termite colony and a naïve Cartesianism that views the self as inner substance. (shrink)

Human beings think of themselves in terms of a privileged non-descriptive designator — a mental “I”. Such thoughts are called “de se” thoughts. The mind/body problem is the problem of deciding what kind of thing I am, and it can be regarded as arising from the fact that we think of ourselves non-descriptively. Why do we think of ourselves in this way? We investigate the functional role of “I” (and also “here” and “now”) in cognition, arguing that the use of (...) such non-descriptive “reflexive” designators is essential for making sophisticated cognition work in a general-purpose cognitive agent. If we were to build a robot capable of similar cognitive tasks as humans, it would have to be equipped with such designators. Once we understand the functional role of reflexive designators in cognition, we will see that to make cognition work properly, an agent must use a de se designator in specific ways in its reasoning. Rather simple arguments based upon how “I” works in reasoning lead to the conclusion that it cannot designate the body or part of the body. If it designates anything, it must be something non-physical. However, for the purpose of making the reasoning work correctly, it makes no difference whether “I” actually designates anything. If we were to build a robot that more or less duplicated human cognition, we would not have to equip it with anything for “I” to designate, and general physicalist inclinations suggest that there would be nothing for “I” to designate in the robot. In particular, it cannot designate the physical contraption. So the robot would believe “I exist”, but it would be wrong. Why should we think we are any different? (shrink)

This chapter argues that Humean analyses do not provide content‐preserving reductions and non‐trivial accounts of the reference. It introduces a distinction between structure in the realm of Being and structure in the representations of Being. The chapter argues that there are good reasons not to expect content‐preserving reductions of the modal to the non‐modal at the level of content, or useful mappings of content‐level structures into structures at the level of Being. In the rest of the chapter, the author deals (...) with the relationship between content‐level structure and structure at the level of Being. The debate between the Humean and non‐Humean should be reconceived as a debate about whether non‐Humean facts play a substantive role in the story of how beliefs about laws and chances are formed and used. (shrink)

On April 1, 2016, at the Annual Meeting of the Pacific Division of the American Philosophical Association, a book symposium, organized by Alyssa Ney, was held in honor of David Albert’s After Physics. All participants agreed that it was a valuable and enlightening session. We have decided that it would be useful, for those who weren’t present, to make our remarks publicly available. Please bear in mind that what follows are remarks prepared for the session, and that on some points (...) participants may have changed their minds in light of the ensuing discussion. (shrink)

We review and discuss the recent monograph by David Wallace on Everettian Quantum Mechanics. This book is a high point of two decades of work on Everett in both physics and philosophy. It is also a beautiful and welcome exemplar of a modern way of doing metaphysics. We discuss certain aspects more critically, and take the opportunity to sketch an alternative pragmatist approach to probability in Everett, to be fully developed elsewhere.

The riddle posed by the double nature of the ego certainly lies beyond [the limits of science]. On the one hand, I am a real individual man, born by a mother anddestined to carrying out real and psychical acts. On the other hand, I am "vision" open toreason, a self-penetrating light, immanent sense-giving consciousness, or how ever you may call it, and as such unique.

Any person truly considering belief in a scientific world view has to confront the question of whether and in what sense, if she views herself as a natural system in a world governed by natural laws, she can continue to regard herself as free. The prima facie clash is usually expressed in terms of a conflict between freedom and determinism, captured in an argument known as the Consequence Argument. If the natural laws are deterministic, our behavior must be deducible by (...) them from the initial conditions of the universe, and we are wrong to think that we exercise regulative control over action. The most common tactic for those who defend the compatibility of freedom and determinism is to deny that regulative control is a requirement of freedom. I will argue that, whether or not regulative control is a requirement of freedom, it is – surprisingly! - compatible with determinism. The discussion here replays themes of the first essay. Personal freedom is a complex concept, embedded in a tangle of criss-crossing personal, social, theological, psychological, and metaphysical debates, each placing its own requirement on the concept, and I make no attempt to address the general question of whether we are free. It is only the specific challenge presented by the Consequence Argument that I address, and that challenge is a clearly defined dynamical issue about the possibility of regulative control over action in a world governed by deterministic laws. (shrink)

Denial of death We don’t like to think about our deaths, and there are cultural developments – social, technological, economic – that make it easier than ever before to live without constant reminders of our mortality. We hide the evidence of death. We live separately from our old people, and quarantine the dying in hospitals and hospices. It’s impolite to mention death in conversation. We view death not as natural and inevitable stage of life, but as a calamity, a mistake, (...) an accident. This attitude towards death isn’t shared by all cultures, and it’s a relatively recent development even in the west. The result of it, however, is a diminished appreciation of the finitude of life. We spend our lives in the way a foolish man spends his fortune as though there will always be more where that came from, Tolstoy, in The Death of Ivan Ilyich, perhaps the most famous literary portrait of the psychology of a dying man, captures how very easy it is – although we all know in an intellectual sense that we all die - to meet our ends with the shock the foolish spender feels when the last dollar is spent. With a sort of desperate plea ‘Nobody told me it was going to end’. Ivan Ilyich (who has sustained a mortal injury in some stupid household chore… putting up a curtain rod) when he begins to acknowledge the signs of his impending death, thinks to himself.. (shrink)

The outstanding stumbling blocks to any reductive account of phenomenal consciousness remain the subjectivity of phenomenal properties and cognitive and epistemic gaps that plague the relationship between physical and phenomenal properties. I suggest that a deflationary interpretation of both is available to defenders of self- representational accounts.

In the general project of trying to reconcile the subjective view of the world (how things seem from the perspective of the embedded agent) with the objective view (the view of the world from the outside, as represented, for example, in our best physics), analytic philosophy, especially in recent years, has been almost solely focused on sensory phenomenology.1 There are two very salient features of the subjective view that haven’t been explored even on the descriptive side but that present prima (...) facie problems at least as great as sensory phenomenology. One is agential phenomenology (the experience of ourselves as agents in the world), and the other is temporal phenomenology. 2 The problems presented by these cases are very different. I want to focus on temporal phenomenology, by which I mean the felt character of a life lived in time. And my goal here is mostly descriptive; I’ll be exploring the question of what it is like to be the kind of being that has a history, that experiences that history in stages, and that keeps a running record of that history as it unfolds. 3 My suggestion is going to be that there is a special phenomenology, not supervenient on the sensory phenomenology, that arises only in the representational setting created by autobiographical memory and that is central to the felt character of a life lived in time. 4 (by autobiographical memory here, I mean not simply what is sometimes referred to as episodic memory - mental images of past experiences - I mean an explicit, account of one’s own history, rendered in explicitly first-personal form. (the difference here is the difference between a perspectival representation centered on the self of the sort that visual experience gives us and an explicit representation of self, of the sort you have, for example when you translate visual experience into a first personal belief like “I am such and such a place, seeing such and such”).. (shrink)

For most of the major philosophers of the seventeenth and eighteenth centuries, human cognition was understood as involving the mind’s reflexive grasp of its own contents. But other important figures have described the very idea of a reflexive thought as incoherent. Ryle notably likened the idea of a reflexive thought to an arm that grasps itself. Recent work in philosophy, psychology, and the cognitive sciences has greatly clarified the special epistemic and semantic properties of reflexive thought. This article is an (...) attempt to give an explicit characterization of the structure of reflexive thoughts that explains those properties and avoids the complaints of its critics. (shrink)

Philosophers of mind tend to take it for granted that causal relations are part of the mind-independent, objective fabric of the physical world. In fact, their status has been hotly contested since Russell famously observed that the closest thing to causal relations in physics are timesymmetric dynamical laws relating global time slices of world-history. 1 These bear a distant relationship to the local, asymmetric relations that form the core of the folk notion of cause. Nancy Cartwright, in an influential response, (...) agreed about the absence of causal relations from physics, but argued that Russell’s position was not viable because agents choosing among potential actions need specifically causal information to distinguish effective from ineffective strategies for bringing about ends. 2 Causal beliefs play an ineliminable role in practical deliberation In recent years, there has been a great deal of progress in understanding the relationship between causal concepts and the dynamical laws that appear in advanced physics, together with a proliferation of new tools for representing and discovering causal structure. (shrink)

Bayesians take “definite” or “single-case” probabilities to be basic. Definite probabilities attach to closed formulas or propositions. We write them here using small caps: PROB(P) and PROB(P/Q). Most objective probability theories begin instead with “indefinite” or “general” probabilities (sometimes called “statistical probabilities”). Indefinite probabilities attach to open formulas or propositions. We write indefinite probabilities using lower case “prob” and free variables: prob(Bx/Ax). The indefinite probability of an A being a B is not about any particular A, but rather about the (...) property of being an A. In this respect, its logical form is the same as that of relative frequencies. For instance, we might talk about the probability of a human baby being female. That probability is about human babies in general — not about individuals. If we examine a baby and determine conclusively that she is female, then the definite probability of her being female is 1, but that does not alter the indefinite probability of human babies in general being female. Most objective approaches to probability tie probabilities to relative frequencies in some way, and the resulting probabilities have the same logical form as the relative frequencies. That is, they are indefinite probabilities. The simplest theories identify indefinite probabilities with relative frequencies.3 It is often objected that such “finite frequency theories” are inadequate because our probability judgments often diverge from relative frequencies. For example, we can talk about a coin being fair (and so the indefinite probability of a flip landing heads is 0.5) even when it is flipped only once and then destroyed (in which case the relative frequency is either 1 or 0). For understanding such indefinite probabilities, it has been suggested that we need a notion of probability that talks about possible instances of properties as well as actual instances.. (shrink)

What is time? What does it mean for time to pass? Is it possible to travel in time? What is the difference between the past and future? Until the work of Newton, these questions were purely topics of philosophical speculation. Since then we've learned a great deal about time, and its study has moved from a subject of philosophical reflection to instead became part of the subject matter of physics. This Very Short Introduction introduces readers to the current physical understanding (...) of the direction of time, from the Second Law of Thermodynamics to the emergence of complexity and life. Jenann Ismael charts the line of development in physical theory from Newton, via Einstein's Theory of Relativity, to the current day. Einstein's innovations led to a vision of time very different from the familiar time of everyday sense. In this new vision, time is one of the dimensions in which the universe is extended alongside the spatial dimensions. The universe appears as a static block of events, in which there is no more a difference between past and future than there is between east and west. Discussing the controversy and philosophical confusion which surrounded the reception of this new vision, Ismael also covers the contemporary mixture of statistical mechanics, cognitive science, and phenomenology that point the way to reconciling the familiar time of everyday sense with the vision of time presented in Einstein's theories."--Amazon.com. (shrink)