Arrow’s impossibility result stems chiefly from a combination of two requirements: independence and fixity. Independence says that the social choice is independent of individual preferences involving unavailable alternatives. Fixity says that the social choice is fixed by a social preference relation that is independent of what is available. Arrow found that requiring, further, that this relation be transitive yields impossibility. Here it is shown that allowing intransitive social indifference still permits only a vastly unsatisfactory system, a liberum veto oligarchy. Arrow’s (...) argument for independence, though, undermines any rationale for fixity. (shrink)

Rawls' Difference Principle asserts that a basic economic structure is just if it makes the worst off people as well off as is feasible. How well off someone is is to be measured by an ‘index’ of ‘primary social goods’. It is this index that gives content to the principle, and Rawls gives no adequate directions for constructing it. In this essay a version of the difference principle is proposed that fits much of what Rawls says, but that makes use (...) of no index. Instead of invoking an index of primary social goods, the principle formulated here invokes a partial ordering of prospects for opportunities. (shrink)

Arrow's Theorem, in its social choice function formulation, assumes that all nonempty finite subsets of the universal set of alternatives is potentially a feasible set. We demonstrate that the axioms in Arrow's Theorem, with weak Pareto strengthened to strong Pareto, are consistent if it is assumed that there is a prespecified alternative which is in every feasible set. We further show that if the collection of feasible sets consists of all subsets of alternatives containing a prespecified list of alternatives and (...) if there are at least three additional alternatives not on this list, replacing nondictatorship by anonymity results in an impossibility theorem. (shrink)

In these three Tanner lectures, distinguished ethical theorist Allan Gibbard explores the nature of normative thought and the bases of ethics. In the first lecture he explores the role of intuitions in moral thinking and offers a way of thinking about the intuitive method of moral inquiry that both places this activity within the natural world and makes sense of it as an indispensable part of our lives as planners. In the second and third lectures he takes up (...) the kind of substantive ethical inquiry he has described in the first lecture, asking how we might live together on terms that none of us could reasonably reject. Since working at cross purposes loses fruits that might stem from cooperation, he argues, any consistent ethos that meets this test would be, in a crucial way, utilitarian. It would reconcile our individual aims to establish, in Kant's phrase, a "kingdom of ends." The volume also contains an introduction by Barry Stroud, the volume editor, critiques by Michael Bratman (Stanford University), John Broome (Oxford University), and F. M. Kamm (Harvard University), and Gibbard's responses. (shrink)

In this volume, F.M. Kamm explores how theories as well as hypothetical and practical cases help us understand rights and their limits. The book begins by considering moral status and its relation to having rights (including whether non-human animals have rights and what rights future persons have). The author then considers whether rights are grounded in duties to oneself, which duties are correlative to rights, and whether neuroscientific and psychological studies can help determine what rights we have. Kamm next investigates (...) the contours of the right not to be harmed by considering critiques of deontological distinctions, the costs that must be undertaken to avoid harming, and a proposal for permissibly harming someone (that allows for resisting the harm) in the Trolley Problem. Additional chapters cover possible implications of the Trolley Problem for such practical issues as correctly programming self-driving cars, providing medical treatments, and enacting redistributive economic policy. Kamm concludes the book by comparing the use of case-based judgments about extreme cases in moral versus aesthetic theory, and by exploring the significance of the right not to be harmed for morally correct policies in the extreme cases of torture and a pandemic. Where pertinent, Kamm considers the views of Derek Parfit, Tom Regan, Christine Korsgaard, Shelly Kagan, Ronald Dworkin, Amartya Sen, Allan Gibbard, Joshua Greene, Arthur Danto, and Judith Thomson, among others."--Provided by publisher. (shrink)

An overview of Bradley's metaphysics and epistemology, which had much of the basic structure of quantum mechanics, but was all but ignored in the years following the formal quantum theories discovered by Heisenberg and Schrödinger. Bradley's version of absolute idealism was infected with the mentalism that was generally associated with idealism in the late nineteenth century. I develop his ideas from a standpoint somewhat more friendly to modern formal methods, although this is not much of a stretch, as Bradley had (...) already taken absolute idealism strongly in that direction, if not all the way. (shrink)

Wittgenstein's philosophies, from both the Tractatus and the Philosophical Investigations, are explained and developed. Wittgenstein uses a primitive version of recursion theory to develop his attempt at a purely logical metaphysics in the Tractatus. However, due to his implicit materialist assumptions, he could not make the system completely logical, and built in a mystical division of possible worlds into the true and the false. This incoherence eventually lead him to reject logic as a method for doing metaphysics, and indeed to (...) reject metaphysics entirely. I argue that his move from the Tractatus to the Investigations was valid, but only given his materialist assumptions. If he had been willing to drop this unnecessary baggage, recursion would have played a very different role in his system, since he would then have had no need to separate static objects from processes, which he saw as purely mental. F.H. Bradley developed such a nonmaterialist metaphysics in the nineteenth century, but was crippled by a mentalism that Wittgenstein was free of. The anti-mentalism and anti-materialism that Wittgenstein considered as given were not so obvious to his predecessor, Russell, who revolted against Bradley's idealism in much the same way Wittgenstein ended up revolting against Russell's logical atomism. In my view, none of these positions was the right approach, which would require nonmentalism and nonmaterialism. But for some reason, these things (which seem to go together quite naturally to me) have been widely considered to be incompatible. Bradley was appropriately a non-materialist, but suffered from mentalism. Russell and the early Wittgenstein were appropriately nonmentalists, but suffered from materialism. The later Wittgenstein was, I would argue, still an ardent materialist and anti-mentalist, in spite of the fact that he had long since realized the contradictions to which materialism leads; he just had not recognized that it was his materialist assumptions that had lead him there, since these assumptions were so firmly engrained in his thinking as to be invisible.. (shrink)

A survey of Kant's views on space, time, geometry and the synthetic nature of mathematics. I concentrate mostly on geometry, but comment briefly on the syntheticity of logic and arithmetic as well. I believe the view of many that Kant's system denied the possibility of non-Euclidean geometries is clearly mistaken, as Kant himself used a non-Euclidean geometry (spherical geometry, used in his day for navigational purposes) in order to explain his idea, which amounts to an anticipation of the later discovery (...) of the general concept of non- Euclidean geometries. Kant's view of geometry and arithmetic as synthetic was, I believe, essentially correct, in that geometry and arithmetic are both synthetic a priori if considered as branches of mathematics independent of the rest of mathematics. However, the view that somehow logic is analytic, while mathematics is synthetic for Kantian reasons, is mistaken. All three disciplines—logic, arithmetic and geometry—are synthetic as disciplines independent from one another. However, they have a common basis, recursion theory, which I prefer to identify with mathematics as a whole. As a result, I do not say, as is often considered to be the Kantian view, that mathematics is synthetic while logic is analytic. Rather, I prefer to say that mathematics is analytic, while logic is synthetic. This is perfectly consistent with Kant's system, since it was arithmetic and geometry individually that he argued were synthetic. What Kant called the analytic is recursion theory, which could be considered as a basic formulation of mathematics or logic—or better, both mathematics and logic could be recognized as essentially the same discipline. However, if "logic" is taken to mean "predicate logic", as is often the case in modern times, then it is mathematics that is closer to Kant's analytic, not logic. Such ambiguities, of course, can be avoided by simply associating Kant's analytic with recursion theory, and avoiding the controversies as to what counts as mathematics or logic.. (shrink)

While the essays on this web site, taken together, explain most of the essentials of my metaphysical system, some material is not covered, and the different essays take quite different approaches. The essays were mostly written for undergraduate and graduate courses in philosophy at the University of Toronto and York University. Thus, each essay is slanted to the issues that were addressed in whatever course it was written for. However, I hope soon to pull all this material together into a (...) cohesive, single work that will explain my system more fully and with more focus, which will serve as my Ph.D. dissertation. In the meantime this brief overview gives the broad picture of what my philosophical system is, and how the various essays on these pages are inter-related. For those who do not wish to read through this entire page, the Quantum Phenomenology essay is probably the one you should read if you only have time to read one, as it is the closest to being comprehensive. (shrink)

Plato's theory of forms is developed and compared to the modern theory of recursion. I show how Plato's theory, as it applies to mathematical objects, is essentially a primitve version of modern recursion theory, which has all the essential elements of the ancient theory. However, Plato himself thought there was more than mathematics to his forms. He believed that form had a noncomposite, unanalyzable component. So, while recursion theory provides an adequate formalization of Plato's theory, it cannot be considered identical (...) to it. I argue--drawing from material in the "Meno," "Phaedo," and "Republic"--that Plato's arguments for noncomposite form are largely fallacious. Plato would, I believe, have taken the computational version developed here seriously, since mathematics was his primary source for clear examples of forms (one could argue that it was his only source short of dipping into mysticism). In fact, there is a long-standing oral tradition that Plato developed a more formal version of his theory in lecture notes for courses he taught at the Academy (the university he founded in Athens). Any such notes, if they existed at all, have been lost. But if such a formal version did exist, it is tantalizing to wonder to what extent Plato may have anticipated modern theoretical computer science and metamathematics. (shrink)

The many worlds anthropic principle is explored here from the a priori perspective of rationalist metaphysics, within the framework of modal logic. It is shown how the apparent contradictions of quantum superposition can be thought of in terms of different levels of world models. The framework of modal logic is used, but given the rationalist assumption that all possible worlds exist. There is thus no absolute distinction between possibility and necessity. To take the point of view of a conscious being (...) in a world, however, is to adopt some such distinction--something we must do in order to do physics. This paper is intended to lay the groundwork for future attempts to develop theories of what is necessarily true in a world with conscious entities. It also contains some tentative speculations on the difficult issue of death and quantum mechanics. (shrink)

Starting with the Descartes' cogito, "I think, therefore I am"--and taking an uncompromisingly rational, rigorously phenomenological approach--I attempt to derive the basic principles of recursion theory (the backbone of all mathematics and logic), and from that the principles of feedback control theory (the backbone of all biology), leading to the basic ideas of quantum mechanics (the backbone of all physics). What is derived is not the full quantum theory, but a basic framework--derived from a priori principles along with common everyday (...) experience--of how the universe of everyday experience should work if it operates according to rational principles. We find, to our surprise, that the resulting system has all the most puzzling features of quantum physics that make physicists scratch their heads. Far from being "bizarre" and "weird", as is usually thought, the strangest paradoxes of quantum theory turn out to be just what one ought to expect of a rational universe. It is the classical, pre-quantum universe of the nineteenth century that has irrational, mystical components. The quantum-mechanics-like theory that is developed is, furthermore, most compatible with the strictest, most uncompromisingly rationalist of the standard interpretations of quantum mechanics, those which add no ad hoc elements to the theory, and which generally trace their history to the relative state formulation of Everett (also called the "many worlds" interpretation). These interpretations take the universe to be quite literally describable as a quantum wavefunction. As with any project this far-reaching in scope, I confess I have had to make some working assumptions along the way. I have attempted to isolate these, and clearly label them as points of possible future revision--they are marked in the text with an asterisk (*). (shrink)

Those who interpret quantum mechanics literally are forced to follow some variant of Everett's relative state formulation (or "many worlds" interpretation). It is generally assumed that this is a rather bizarre result that many physicists (especially cosmologists) have been forced into because of the evidence. I look at the history of philosophy, however, reveals that rationalism has always flirted with this very idea, from Parmenides to Leibniz to modern times. I will survey some of the philosophical history, and show how (...) the so-called paradox of quantum superposition can be considered a consequence of basic rationalist assumptions such as the principle of sufficient reason and the identity of indiscernibles. (shrink)

The Latin religious text known in the Middle Ages as the Stimulus Amoris must be considered a key text of late-medieval Franciscan spirituality, and one of the texts from the Franciscan milieu that was most widely copied and disseminated throughout the Middle Ages among monastic as well as lay readerships.1 In a recent study, Falk Eisermann has demonstrated that the Stimulus Amoris was subject to a particularly productive reception with multiple adaptations through centuries, and that the text to a large (...) extent was without one clearly discernible, normative form. The Stimulus Amoris, in other words, appears to have been regarded as an open text that could be, and in fact was altered, excerpted, shortened and... (shrink)

On an individualist view of testimonial justification, a subject’s belief based on testimony is justified ultimately on the basis of nontestimonial beliefs alone. The prevailing version of individualism has been inductive individualism, according to which the nontestimonial basis for a testimonial belief is an inductively based belief in the reliability of the testifier. Here I consider an alternative to inductive individualism, which I call the parity account. This is the view, endorsed in various forms by Allan Gibbard, Richard (...) Foley and Keith Lehrer, that my testimonial beliefs have epistemic standing because there is a cognitive parity between me and others. I may trust the beliefs of others because I may trust my own beliefs. I focus on an argument central to Lehrer’s account: I am worthy of my trust in what I believe; others are as worthy of my trust in what they believe as I am in what I believe; so others are worthy of my trust in what they believe. I examine whether this argument can justify my testimonial beliefs. If the parity account is to succeed, the premises of the argument need support. I criticize diverse ways of supporting the premises suggested by Lehrer and by remarks of Foley. I conclude that the parity argument cannot account for the justification of all my testimonial beliefs. It is at best an adjunct argument that depends for its force on prior justified testimonial beliefs.Author Keywords: Testimony; Justification; Parity; Trust; Individualism; Skepticism. (shrink)

This book examines some of the deepest questions in philosophy: What is involved in judging a belief, action, or feeling to be rational?

An original and elegant work of metaethics, this book brings a new clarity and rigor to the discussion of these tangled issues, and will significantly alter the ...

Choices can be wise or foolish, and feelings can be apt or off the mark. So we judge, and it would be good to know what content these normative judgements carry. Gibbard offers an answer, and elaborates it. His theory explores what is at issue in narrowly moral questions, and in questions of rational thought and conduct in general.

The concepts of meaning and mental content resist naturalistic analysis. This is because they are normative: they depend on ideas of how things ought to be. Allan Gibbard offers an expressivist explanation of these 'oughts': he borrows devices from metaethics to illuminate deep problems at the heart of the philosophy of language and thought.

Identities formed with proper names may be contingent. this claim is made first through an example. the paper then develops a theory of the semantics of concrete things, with contingent identity as a consequence. this general theory lets concrete things be made up canonically from fundamental physical entities. it includes theories of proper names, variables, cross-world identity with respect to a sortal, and modal and dispositional properties. the theory, it is argued, is coherent and superior to its rivals, in that (...) it stems naturally from a systematic picture of the physical world. (shrink)

Philosophers have long suspected that thought and discourse about what we ought to do differ in some fundamental way from statements about what is. But the difference has proved elusive, in part because the two kinds of statement look alike. Focusing on judgments that express decisions--judgments about what is to be done, all things considered--Allan Gibbard offers a compelling argument for reconsidering, and reconfiguring, the distinctions between normative and descriptive discourse--between questions of "ought" and "is." Gibbard considers (...) how our actions, and our realities, emerge from the thousands of questions and decisions we form for ourselves. The result is a book that investigates the very nature of the questions we ask ourselves when we ask how we should live, and that clarifies the concept of "ought" by understanding the patterns of normative concepts involved in beliefs and decisions. An original and elegant work of metaethics, this book brings a new clarity and rigor to the discussion of these tangled issues, and will significantly alter the long-standing debate over "objectivity" and "factuality" in ethics. Table of Contents: I. Preliminaries 1. Introduction: A Possibility Proof 2. Intuitionism as Template: Emending Moore II. The Thing to Do 3. Planning and Ruling Out: The "Frege-Geach" Problem 4. Judgment, Disagreement, Negation 5. Supervenience and Constitution 6. Character and Import III. Normative Concepts 7. Ordinary Oughts: Meaning and Motivation 8. Normative Kinds: Patterns of Engagement 9. What to Say about the Thing to Do: The Expressivistic Turn and What it Gains Us IV. Knowing What to Do 10. Explaining with Plans 11. Knowing What to Do 12. Ideal Response Concepts 13. Deep Vindication and Practical Confidence 14. Impasse and Dissent References Index This is a remarkable book. It takes up a central and much-discussed problem - the difference between normative thought and "descriptive" thought. It develops a compelling response to that problem with ramifications for much else in philosophy. But perhaps most importantly, it brings new clarity and rigor to the discussion of these tangled issues. It will take some time to come to terms with the details of Gibbard's discussion. It is absolutely clear, however, that the book will reconfigure the debate over objectivity and "factuality" in ethics. --Gideon Rosen, Professor of Philosophy, Princeton University Gibbard,/author> writes elegantly, and the theory he develops is innovative, philosophically sophisticated, and challenging. Gibbard defends his theory vigorously and with admirable intellectual honesty. --David Copp, Professor of Philosophy, Bowling Green State University. (shrink)

The concepts of meaning and mental content resist naturalistic analysis. This is because they are normative: they depend on ideas of how things ought to be.

What are ethical judgments about? And what is their relation to practice? How can ethical judgment aspire to objectivity? The past two decades have witnessed a resurgence of interest in metaethics, placing questions such as these about the nature and status of ethical judgment at the very center of contemporary moral philosophy. Moral Discourse and Practice: Some Philosophical Approaches is a unique anthology which collects important recent work, much of which is not easily available elsewhere, on core metaethical issues. Naturalist (...) moral realism, once devastated by the charge of "naturalistic fallacy," has been reinvigorated, as have versions of moral realism that insist on the discontinuity between ethics and science. Irrealist, expressivist programs have also developed with great subtlety, encouraging the thought that a noncognivist account may actually be able to explain ethical judgments' aspirations to objectivity. Neo-Kantian constructivist theories have flourished as well, offering hope that morality can be grounded in a plausible conception of reasonable conduct. Together, the positions advanced in the essays collected here address these recent developments, constituting a rich array of approaches to contemporary moral philosophy's most fundamental debates. An extensive introduction by Darwall, Gibbard, and Railton is also included, making this volume the most comprehensive and up-to-date work of its kind. Moral Discourse is ideally suited for use in courses in contemporary ethics, ethical theory, and metaethics. (shrink)