Like biological species, languages change over time. As noted by Darwin, there are many parallels between language evolution and biological evolution. Insights into these parallels have also undergone change in the past 150 years. Just like genes, words change over time, and language evolution can be likened to genome evolution accordingly, but what kind of evolution? There are fundamental differences between eukaryotic and prokaryotic evolution. In the former, natural variation entails the gradual accumulation of minor mutations in alleles. In (...) the latter, lateral gene transfer is an integral mechanism of natural variation. The study of language evolution using biological methods has attracted much interest of late, most approaches focusing on language tree construction. These approaches may underestimate the important role that borrowing plays in language evolution. Network approaches that were originally designed to study lateral gene transfer may provide more realistic insights into the complexities of language evolution.Editor's suggested further reading in BioEssaysLinguistic evidence supports date for Homeric epics Abstract. (shrink)

There is a substantial class of collective decision problems whose successful solution requires interdependence among decision makers at the agenda-setting stage and independence at the stage of choice. We define this class of problems and describe and apply a search-and-decision mechanism theoretically modeled in the context of honeybees and identified in earlier empirical work in biology. The honeybees’ mechanism has useful implications for mechanism design in human institutions, including courts, legislatures, executive appointments, research and development in firms, and basic research (...) in the sciences. Our paper offers a fresh perspective on the idea of “biomimicry” in institutional design and raises the possibility of comparative institutional analysis across species. (shrink)

In this note, I correct an error in List (2003). I warmly thank Ron Holzman for drawing my attention to this error, and Franz Dietrich for giving me some key insights that have led to the present correction, particularly the formulation of assumption (a*) below. Theorem 2 (speci…cally, the claim that (i) implies (ii) and the associated Proposition 2) in List (2003) requires an additional assumption on the set X of propositions under consideration (the agenda). Let me use (...) the de…nitions and notation from List (2003). Also, de…ne a set of propositions to be satis…able if some truth-value assignment makes all its members true, and, for each Y X, de…ne Y : := f: : 2Yg. In List (2003), I assumed that (a) X contains at least two distinct atomic propositions P; Q and their conjunction (P ^ Q), and (b) X contains proposition-negation pairs (i.e. if 2 X, then : 2 X, where :: is identi…ed with ). While assumption (b) is correct as stated, Theorem 2 requires assumption (a*) instead of (a). (shrink)

Lists of species underpin many fields of human endeavour, but there are currently no universally accepted principles for deciding which biological species should be accepted when there are alternative taxonomic treatments (and, by extension, which scientific names should be applied to those species). As improvements in information technology make it easier to communicate, access, and aggregate biodiversity information, there is a need for a framework that helps taxonomists and the users of taxonomy decide which taxa and names (...) should be used by society whilst continuing to encourage taxonomic research that leads to new species discoveries, new knowledge of species relationships, and the refinement of existing species concepts. Here, we present 10 principles that can underpin such a governance framework, namely (i) the species list must be based on science and free from nontaxonomic considerations and interference, (ii) governance of the species list must aim for community support and use, (iii) all decisions about list composition must be transparent, (iv) the governance of validated lists of species is separate from the governance of the names of taxa, (v) governance of lists of accepted species must not constrain academic freedom, (vi) the set of criteria considered sufficient to recognise species boundaries may appropriately vary between different taxonomic groups but should be consistent when possible, (vii) a global list must balance conflicting needs for currency and stability by having archived versions, (viii) contributors need appropriate recognition, (ix) list content should be traceable, and (x) a global listing process needs both to encompass global diversity and to accommodate local knowledge of that diversity. We conclude by outlining issues that must be resolved if such a system of taxonomic list governance and a unified list of accepted scientific names generated are to be universally adopted. (shrink)

The Endangered Species Act of 1973 (ESA) is America's strongest environmental law. Its citizen-suit provisionany personawards implicit intrinsic value, de facto standing, and operational legal rights (sensu Christopher D. Stone) to listed species. Accordingly, some cases had gone forward in the federal courts in the name of various listed species between 1979 (Palila v. Hawaii Dept. of Land & Natural Resources) and 2004 (Cetacean Community v. Bush), when the Ninth Circuit Court of Appeals ruled that animals could (...) not sue in their own name. Because the Supreme Court has interpreted its habitat destruction as the of a listed species, some have argued that enforcement of the ESA's critical-habitat-protection provision is a of private property without just compensation, contrary to the Fifth Amendment of the Constitution. The courts have not agreed. The ESA citizen-suit provision appears to waive federal-court standing requirements devolved from Article III of the U.S. Constitution, creating much confusion and mutually contradictory rulings. A series of cases (culminating with Bennett v. Spear) reconciles the ESA's citizen-suit provision with the particularized and concrete standing requirements devolved from Article III. (shrink)

The Endangered Species Act of 1973 is America's strongest environmental law. Its citizen-suit provision—permitting “any person” whomsoever to sue on behalf of a threatened or endangered species—awards implicit intrinsic value, de facto standing, and operational legal rights to listed species. Accordingly, some cases had gone forward in the federal courts in the name of various listed species between 1979 and 2004, when the Ninth Circuit Court of Appeals ruled that animals could not sue in their own (...) name. Because the Supreme Court has interpreted its habitat destruction as the “taking” of a listed species, some have argued that enforcement of the ESA's critical-habitat-protection provision is a “regulatory taking” of private property without just compensation, contrary to the Fifth Amendment of the Constitution. The courts have not agreed. The ESA citizen-suit provision appears to waive federal-court standing requirements devolved from Article III of the U.S. Constitution, creating much confusion and mutually contradictory rulings. A series of cases reconciles the ESA's citizen-suit provision with the particularized and concrete “injury-in-fact” standing requirements devolved from Article III. (shrink)

Frank E. Zachos offers a comprehensive review of one of today's most important and contentious issues in biology: the species problem. After setting the stage with key background information on the topic, the book provides a brief history of species concepts from antiquity to the Modern Synthesis, followed by a discussion of the ontological status of species with a focus on the individuality thesis and potential means of reconciling it with other philosophical approaches. More than 30 different (...) species concepts found in the literature are presented in an annotated list, and the most important ones, including the Biological, Genetic, Evolutionary and different versions of the Phylogenetic Species Concept, are discussed in more detail. Specific questions addressed include the problem of asexual and prokaryotic species, intraspecific categories like subspecies and Evolutionarily Significant Units, and a potential solution to the species problem based on a hierarchical approach that distinguishes between ontological and operational species concepts. A full chapter is dedicated to the challenge of delimiting species by means of a discrete taxonomy in a continuous world of inherently fuzzy boundaries. Further, the book outlines the practical ramifications for ecology and evolutionary biology of how we define the species category, highlighting the danger of an apples and oranges problem if what we subsume under the same name ("species") is in actuality a variety of different entities. A succinct summary chapter, glossary and annotated list of references round out the coverage, making the book essential reading for all biologists looking for an accessible introduction to the historical, philosophical and practical dimensions of the species problem. (shrink)

The ability to appropriately sequence a list of discrete items is an important facet in performing routine cognitive tasks and may play a significant role in the acquisition of early communication skills. Though the serial learning abilities of some species, such as chimpanzees and rhesus macaques are well documented, there is virtually no information on the extent of these skills with gorillas. In this study, a young female western lowland gorilla has demonstrated the ability to learn a (...) class='Hi'>list of seven Arabic numerals by selecting them on a monitor behind an infrared touchframe. As list length increased, Rollie required fewer trials to reach the criterion, suggesting an acquisition of skills associated with serial learning. Rollie was most likely to correctly select the first item in the sequence and least likely to select the penultimate item in the sequence. Her performance suggests serial learning abilities in the range of other non-verbal species and provides preliminary evidence that supports the assertion that gorillas can succeed at this form of serial learning task. (shrink)

The nature of science is a primary goal in school science. Most teachers are not well-prepared for teaching NOS, but a sophisticated and in-depth understanding of NOS is necessary for effective teaching. Some authors emphasize the need for teaching NOS in context. Species, a central concept in biology, is proposed in this article as a concrete example of a means for achieving increased understanding of NOS. Although species are commonly presented in textbooks as fixed entities with a single (...) definition, the concept of species is a highly discussed one in the science and the philosophy of biology. A multitude of species concepts exist, reflecting both the views and interests of researchers and their utility in different organism groups. The present study serves to address the following questions: How do textbooks in Norwegian primary and lower secondary schools present the concept of species? Can inquiries into the concept of “species” serve to highlight aspects of NOS? A review of the available literature on species and species concepts in school is also performed. In the schoolbooks, the biological species concept is commonly used as the main definition, whereas the morphological species concept is represented by additional remarks of similarity. The potential and pitfalls of using the species concept for teaching NOS are discussed, with NOS being discussed both as a family resemblance concept and as a consensus list. Teacher education is proposed as a starting point for inducing a more sophisticated view of biology into schools. (shrink)

This book is about the philosophy of de-extinction. -/- CHAPTER 1 introduces the two main philosophical questions that are raised by the prospect of extinct species being brought back from the dead—namely, the ‘Authenticity Question’ and the ‘Ethical Question’. It distinguishes the many different types and methods of de-extinction. Finally, it examines the aims of wildlife conservation with a view to whether they are compatible with de-extinction, or not. -/- CHAPTER 2 examines three prime candidates for de-extinction—namely, the aurochs, (...) the woolly mammoth, and the passenger pigeon. It is about what these animals were like, why people want to resurrect them, and the methods by which their resurrections could be accomplished. -/- CHAPTER 3 is about the authenticity of de-extinct animals. Critics of de-extinction have offered many reasons for thinking that the products of de-extinction will be inauthentic. The bulk of the chapter is taken up with surveying their arguments. We attempt to show that none are convincing, and end the chapter by offering and defending two arguments in favour of the view that authentic de-extinctions are possible. -/- CHAPTER 4 surveys and critically evaluates all the main arguments both for and against de-extinction. It presents a qualified defence of the claim that conservationists should embrace de-extinction. It ends with a list of do’s and don’ts for conservationist de-extinction projects. (shrink)

In this paper, I argue that no theory of consciousness can simultaneously respect four initially plausible metaphysical claims – namely, ‘first-person realism’, ‘non-solipsism’, ‘non-fragmentation’, and ‘one world’ – but that any three of the four claims are mutually consistent. So, theories of consciousness face a ‘quadrilemma’. Since it will be hard to achieve a consensus on which of the four claims to retain and which to give up, we arrive at a landscape of competing theories, all of which have pros (...) and cons. I will briefly indicate which kinds of theories correspond to the four horns of the quadrilemma. (shrink)

One of the hallmark themes of Karl Popper’s approach to the social sciences was the insistence that when social scientists are members of the society they study, then they are liable to affect that society. In particular, they are liable to affect it in such a way that the claims they make lose their validity. “The interaction between the scientist’s pronouncements and social life almost invariably creates situations in which we have not only to consider the truth of such pronouncements, (...) but also their actual influence on future developments. The social scientist may be striving to find the truth; but, at the same time, he must always be exerting a definite influence upon society. The very fact that his pronouncements do exert an influence destroys their objectivity.” (Popper 1963. (shrink)

Are companies, churches, and states genuine agents? Or are they just collections of individuals that give a misleading impression of unity? This question is important, since the answer dictates how we should explain the behaviour of these entities and whether we should treat them as responsible and accountable on the model of individual agents. Group Agency offers a new approach to that question and is relevant, therefore, to a range of fields from philosophy to law, politics, and the social sciences. (...) Christian List and Philip Pettit argue that there really are group or corporate agents, over and above the individual agents who compose them, and that a proper approach to the social sciences, law, morality, and politics must take account of this fact. Unlike some earlier defences of group agency, their account is entirely unmysterious in character and, despite not being technically difficult, is grounded in cutting-edge work in social choice theory, economics, and philosophy. (shrink)

This paper generalises the classical Condorcet jury theorem from majority voting over two options to plurality voting over multiple options. The paper further discusses the debate between epistemic and procedural democracy and situates its formal results in that debate. The paper finally compares a number of different social choice procedures for many-option choices in terms of their epistemic merits. An appendix explores the implications of some of the present mathematical results for the question of how probable majority cycles (as in (...) Condorcet's paradox) are in large electorates. (shrink)

It is often argued that higher-level special-science properties cannot be causally efficacious since the lower-level physical properties on which they supervene are doing all the causal work. This claim is usually derived from an exclusion principle stating that if a higher-level property F supervenes on a physical property F* that is causally sufficient for a property G, then F cannot cause G. We employ an account of causation as difference-making to show that the truth or falsity of this principle is (...) a contingent matter and derive necessary and sufficient conditions under which a version of it holds. We argue that one important instance of the principle, far from undermining non-reductive physicalism, actually supports the causal autonomy of certain higher-level properties. (shrink)

This transcription of notes made by Charles Darwin during the voyage of H. M. S. Beagle records his observations of the animals and plants that he encountered, and provides a valuable insight into the intellectual development of one of our most influential scientists. Darwin drew on many of these notes for his well known Journal of Researches (1839), but the majority of them have remained unpublished. This volume provides numerous examples of his unimpeachable accuracy in describing the wide range of (...) animals seen in the course of his travels, and of his closely analytical approach towards every one of his observations. Only at the very end of the voyage were his first doubts about the immutability of species expressed consciously, but here are to be found the initial seeds of his theory of evolution, and of the fields of behavioural and ecological study of which he was one of the founding fathers. (shrink)

Are groups ever capable of bearing responsibility, over and above their individual members? This chapter discusses and defends the view that certain organized collectives – namely, those that qualify as group moral agents – can be held responsible for their actions, and that group responsibility is not reducible to individual responsibility. The view has important implications. It supports the recognition of corporate civil and even criminal liability in our legal systems, and it suggests that, by recognizing group agents as loci (...) of responsibility, we may be able to avoid “responsibility gaps” in some cases of collectively caused harms for which there is a shortfall of individual responsibility. The chapter further asks whether the view that certain groups are responsible agents commits us to the view that those groups should also be given rights of their own and gives a qualified negative answer. (shrink)

This item was published as 'Appendix 3: An Implication of the k-option Condorcet jury mechanism for the probability of cycles' in List and Goodin (2001) http://eprints.lse.ac.uk/705/. Standard results suggest that the probability of cycles should increase as the number of options increases and also as the number of individuals increases. These results are, however, premised on a so-called "impartial culture" assumption: any logically possible preference ordering is assumed to be as likely to be held by an individual as any (...) other. The present chapter shows, in the three-option case, that given suitably systematic, however slight, deviations from an impartial culture situation, the probability of a cycle converges either to zero (more typically) or to one (less typically) as the number of individuals increases. (shrink)

This paper provides an introductory review of the theory of judgment aggregation. It introduces the paradoxes of majority voting that originally motivated the field, explains several key results on the impossibility of propositionwise judgment aggregation, presents a pedagogical proof of one of those results, discusses escape routes from the impossibility and relates judgment aggregation to some other salient aggregation problems, such as preference aggregation, abstract aggregation and probability aggregation. The present illustrative rather than exhaustive review is intended to give readers (...) new to the field of judgment aggregation a sense of this rapidly growing research area. (shrink)

The exclusion argument is widely thought to put considerable pressure on dualism, if not to refute it outright. We argue to the contrary that, whether or not their position is ultimately true, dualists have a plausible response. The response focuses on the notion of ‘distinctness’ that is employed to distinguish between mental and physical properties: if ‘distinctness’ is understood in one way, the exclusion principle on which the argument rests can be denied by the dualist; if it is understood in (...) another way, the argument is not persuasive. (shrink)

Philosophers have argued about the nature and the very existence of free will for centuries. Today, many scientists and scientifically minded commentators are skeptical that it exists, especially when it is understood to require the ability to choose between alternative possibilities. If the laws of physics govern everything that happens, they argue, then how can our choices be free? Believers in free will must be misled by habit, sentiment, or religious doctrine. Why Free Will Is Real defies scientific orthodoxy and (...) presents a bold new defense of free will in the same naturalistic terms that are usually deployed against it. -/- Unlike those who defend free will by giving up the idea that it requires alternative possibilities to choose from, Christian List retains this idea as central, resisting the tendency to defend free will by watering it down. He concedes that free will and its prerequisites—intentional agency, alternative possibilities, and causal control over our actions—cannot be found among the fundamental physical features of the natural world. But, he argues, that’s not where we should be looking. Free will is a “higher-level” phenomenon found at the level of psychology. It is like other phenomena that emerge from physical processes but are autonomous from them and not best understood in fundamental physical terms—like an ecosystem or the economy. When we discover it in its proper context, acknowledging that free will is real is not just scientifically respectable; it is indispensable for explaining our world. (shrink)

This paper provides an introductory review of the theory of judgment aggregation. It introduces the paradoxes of majority voting that originally motivated the field, explains several key results on the impossibility of propositionwise judgment aggregation, presents a pedagogical proof of one of those results, discusses escape routes from the impossibility and relates judgment aggregation to some other salient aggregation problems, such as preference aggregation, abstract aggregation and probability aggregation. The present illustrative rather than exhaustive review is intended to give readers (...) new to the field of judgment aggregation a sense of this rapidly growing research area. (shrink)

The aim of this paper is to discuss a seemingly straightforward argument against physicalism which, despite being implicit in much of the philosophical debate about consciousness, has not received the attention it deserves (compared to other, better-known “epistemic”, “modal”, and “conceivability” arguments). This is the argument from the non-supervenience of the first-personal (and indexical) facts on the third-personal (and non-indexical) ones. This non-supervenience, together with the assumption that the physical facts (as conventionally understood) are third-personal, entails that some facts – (...) namely, first-personal, phenomenal ones – do not supervene on the physical facts. Unlike other arguments against physicalism, the first-personal argument, if successful, refutes not only physicalism but also other third-personal metaphysical pictures, including standard versions of dualism. (shrink)

Suppose that the members of a group each hold a rational set of judgments on some interconnected questions, and imagine that the group itself has to form a collective, rational set of judgments on those questions. How should it go about dealing with this task? We argue that the question raised is subject to a difficulty that has recently been noticed in discussion of the doctrinal paradox in jurisprudence. And we show that there is a general impossibility theorem that that (...) difficulty illustrates. Our paper describes this impossibility result and provides an exploration of its significance. The result naturally invites comparison with Kenneth Arrow's famous theorem (Arrow, 1963 and 1984; Sen, 1970) and we elaborate that comparison in a companion paper (List and Pettit, 2002). The paper is in four sections. The first section documents the need for various groups to aggregate its members' judgments; the second presents the discursive paradox; the third gives an informal statement of the more general impossibility result; the formal proof is presented in an appendix. The fourth section, finally, discusses some escape routes from that impossibility. (shrink)

I argue that free will and determinism are compatible, even when we take free will to require the ability to do otherwise and even when we interpret that ability modally, as the possibility of doing otherwise, and not just conditionally or dispositionally. My argument draws on a distinction between physical and agential possibility. Although in a deterministic world only one future sequence of events is physically possible for each state of the world, the more coarsely defined state of an agent (...) and his or her environment can be consistent with more than one such sequence, and thus different actions can be “agentially possible”. The agential perspective is supported by our best theories of human behaviour, and so we should take it at face value when we refer to what an agent can and cannot do. On the picture I defend, free will is not a physical phenomenon, but a higher-level one on a par with other higher-level phenomena such as agency and intentionality. (shrink)

The aim of this exploratory paper is to review an under-appreciated parallel between group agency and artificial intelligence. As both phenomena involve non-human goal-directed agents that can make a difference to the social world, they raise some similar moral and regulatory challenges, which require us to rethink some of our anthropocentric moral assumptions. Are humans always responsible for those entities’ actions, or could the entities bear responsibility themselves? Could the entities engage in normative reasoning? Could they even have rights and (...) a moral status? I will tentatively defend the (increasingly widely held) view that, under certain conditions, artificial intelligent systems, like corporate entities, might qualify as responsible moral agents and as holders of limited rights and legal personhood. I will further suggest that regulators should permit the use of autonomous artificial systems in high-stakes settings only if they are engineered to function as moral (not just intentional) agents and/or there is some liability-transfer arrangement in place. I will finally raise the possibility that if artificial systems ever became phenomenally conscious, there might be a case for extending a stronger moral status to them, but argue that, as of now, this remains very hypothetical. (shrink)

Scientists and philosophers frequently speak about levels of description, levels of explanation, and ontological levels. This paper presents a framework for studying levels. I give a general definition of a system of levels and discuss several applications, some of which refer to descriptive or explanatory levels while others refer to ontological levels. I illustrate the usefulness of this framework by bringing it to bear on some familiar philosophical questions. Is there a hierarchy of levels, with a fundamental level at the (...) bottom? And what does the answer to this question imply for physicalism, the thesis that everything supervenes on the physical? Are there emergent higher-level properties? Are higher-level descriptions reducible to lower-level ones? Can the relationship between normative and non-normative domains be viewed as one involving levels? And might a levelled framework shed light on the relationship between third-personal and first-personal phenomena? (shrink)

Our aim in this survey article is to provide an accessible overview of some key results and questions in the theory of judgment aggregation. We omit proofs and technical details, focusing instead on concepts and underlying ideas.

The pore‐forming BCL‐2 family proteins are effectors of mitochondrial poration in apoptosis initiation. Two atypical effectors—BOK and truncated BID (tBID)—join the canonical effectors BAK and BAX. Gene knockout revealed developmental phenotypes in the absence the effectors, supporting their roles in vivo. During apoptosis effectors are activated and change shape from dormant monomers to dynamic oligomers that associate with and permeabilize mitochondria. BID is activated by proteolysis, BOK accumulates on inhibition of its degradation by the E3 ligase gp78, while BAK and (...) BAX undergo direct activation by BH3‐only initiators, autoactivation, and crossactivation. Except tBID, effector oligomers on the mitochondria appear as arcs and rings in super‐resolution microscopy images. The BH3‐in‐groove dimers of BAK and BAX, the tBID monomers, and uncharacterized BOK species are the putative building blocks of apoptotic pores. Effectors interact with lipids and bilayers but the mechanism of membrane poration remains elusive. I discuss effector‐mediated mitochondrial poration. (shrink)

This paper sketches a new and somewhat heterodox metaphysical theory of consciousness: the “many-worlds theory”. It drops the assumption that all conscious subjects’ experiences are features of one and the same world and instead associates different subjects with different “first-personally centred worlds”. We can think of these as distinct “first-personal realizers” of a shared “third-personal world”, where the latter is supervenient, in a sense to be explained. This is combined with a form of modal realism, according to which different subjects’ (...) first-personally centred worlds are all real, though only one of them is present for each subject. The theory offers a novel way of capturing the irreducibly subjective nature of conscious experience without lapsing into solipsism. The paper also looks at some scientific theories of consciousness, such as integrated information theory, through the proposed lens and reconsiders the hard problem of consciousness. (shrink)

We offer a critical assessment of the “exclusion argument” against free will, which may be summarized by the slogan: “My brain made me do it, therefore I couldn't have been free”. While the exclusion argument has received much attention in debates about mental causation (“could my mental states ever cause my actions?”), it is seldom discussed in relation to free will. However, the argument informally underlies many neuroscientific discussions of free will, especially the claim that advances in neuroscience seriously challenge (...) our belief in free will. We introduce two distinct versions of the argument, discuss several unsuccessful responses to it, and then present our preferred response. This involves showing that a key premise – the “exclusion principle” – is false under what we take to be the most natural account of causation in the context of agency: the difference-making account. We finally revisit the debate about neuroscience and free will. (shrink)

The existence of group agents is relatively widely accepted. Examples are corporations, courts, NGOs, and even entire states. But should we also accept that there is such a thing as group consciousness? I give an overview of some of the key issues in this debate and sketch a tentative argument for the view that group agents lack phenomenal consciousness. In developing my argument, I draw on integrated information theory, a much-discussed theory of consciousness. I conclude by pointing out an implication (...) of my argument for the normative status of group agents. (shrink)

Scientists and philosophers frequently speak about levels of description, levels of explanation, and ontological levels. In this paper, I propose a unified framework for modelling levels. I give a general definition of a system of levels and show that it can accommodate descriptive, explanatory, and ontological notions of levels. I further illustrate the usefulness of this framework by applying it to some salient philosophical questions: (1) Is there a linear hierarchy of levels, with a fundamental level at the bottom? And (...) what does the answer to this question imply for physicalism, the thesis that everything supervenes on the physical? (2) Are there emergent properties? (3) Are higher-level descriptions reducible to lower-level ones? (4) Can the relationship between normative and non-normative domains be viewed as one involving levels? Although I use the terminology of “levels”, the proposed framework can also represent “scales”, “domains”, or “subject matters”, where these are not linearly but only partially ordered by relations of supervenience or inclusion. (shrink)

The two most influential traditions of contemporary theorizing about democracy, social choice theory and deliberative democracy, are generally thought to be at loggerheads, in that the former demonstrates the impossibility, instability or meaninglessness of the rational collective outcomes sought by the latter. We argue that the two traditions can be reconciled. After expounding the central Arrow and Gibbard-Satterthwaite impossibility results, we reassess their implications, identifying the conditions under which meaningful democratic decision making is possible. We argue that deliberation can promote (...) these conditions, and hence that social choice theory suggests not that democratic decision making is impossible, but rather that democracy must have a deliberative aspect. (shrink)

Political science is divided between methodological individualists, who seek to explain political phenomena by reference to individuals and their interactions, and holists (or nonreductionists), who consider some higher-level social entities or properties such as states, institutions, or cultures ontologically or causally significant. We propose a reconciliation between these two perspectives, building on related work in philosophy. After laying out a taxonomy of different variants of each view, we observe that (i) although political phenomena result from underlying individual attitudes and behavior, (...) individual-level descriptions do not always capture all explanatorily salient properties, and (ii) nonreductionistic explanations are mandated when social regularities are robust to changes in their individual-level realization. We characterize the dividing line between phenomena requiring nonreductionistic explanation and phenomena permitting individualistic explanation and give examples from the study of ethnic conflicts, social-network theory, and international-relations theory. (shrink)

We offer a new argument for the claim that there can be non-degenerate objective chance (“true randomness”) in a deterministic world. Using a formal model of the relationship between different levels of description of a system, we show how objective chance at a higher level can coexist with its absence at a lower level. Unlike previous arguments for the level-specificity of chance, our argument shows, in a precise sense, that higher-level chance does not collapse into epistemic probability, despite higher-level properties (...) supervening on lower-level ones. We show that the distinction between objective chance and epistemic probability can be drawn, and operationalized, at every level of description. There is, therefore, not a single distinction between objective and epistemic probability, but a family of such distinctions. (shrink)

Much recent philosophical work on social freedom focuses on whether freedom should be understood as non-interference, in the liberal tradition associated with Isaiah Berlin, or as non-domination, in the republican tradition revived by Philip Pettit and Quentin Skinner. We defend a conception of freedom that lies between these two alternatives: freedom as independence. Like republican freedom, it demands the robust absence of relevant constraints on action. Unlike republican, and like liberal freedom, it is not moralized. We show that freedom as (...) independence retains the virtues of its liberal and republican counterparts while shedding their vices. Our aim is to put this conception of freedom more firmly on the map and to offer a novel perspective on the logical space in which different conceptions of freedom are located. (shrink)

In solving judgment aggregation problems, groups often face constraints. Many decision problems can be modelled in terms the acceptance or rejection of certain propositions in a language, and constraints as propositions that the decisions should be consistent with. For example, court judgments in breach-of-contract cases should be consistent with the constraint that action and obligation are necessary and sufficient for liability; judgments on how to rank several options in an order of preference with the constraint of transitivity; and judgments on (...) budget items with budgetary constraints. Often more or less demanding constraints on decisions are imaginable. For instance, in preference ranking problems, the transitivity constraint is often contrasted with the weaker acyclicity constraint. In this paper, we make constraints explicit in judgment aggregation by relativizing the rationality conditions of consistency and deductive closure to a constraint set, whose variation yields more or less strong notions of rationality. We review several general results on judgment aggregation in light of such constraints. (shrink)

In normative political theory, it is widely accepted that democracy cannot be reduced to voting alone, but that it requires deliberation. In formal social choice theory, by contrast, the study of democracy has focused primarily on the aggregation of individual opinions into collective decisions, typically through voting. While the literature on deliberation has an optimistic flavour, the literature on social choice is more mixed. It is centred around several paradoxes and impossibility results identifying conflicts between different intuitively plausible desiderata. In (...) recent years, there has been a growing dialogue between the two literatures. This paper discusses the connections between them. Important insights are that (i) deliberation can complement aggregation and open up an escape route from some of its negative results; and (ii) the formal models of social choice theory can shed light on some aspects of deliberation, such as the nature of deliberation-induced opinion change. (shrink)

The ``doctrinal paradox'' or ``discursive dilemma'' shows that propositionwise majority voting over the judgments held by multiple individuals on some interconnected propositions can lead to inconsistent collective judgments on these propositions. List and Pettit (2002) have proved that this paradox illustrates a more general impossibility theorem showing that there exists no aggregation procedure that generally produces consistent collective judgments and satisfies certain minimal conditions. Although the paradox and the theorem concern the aggregation of judgments rather than preferences, they invite (...) comparison with two established results on the aggregation of preferences: the Condorcet paradox and Arrow's impossibility theorem. We may ask whether the new impossibility theorem is a special case of Arrow's theorem, or whether there are interesting disanalogies between the two results. In this paper, we compare the two theorems, and show that they are not straightforward corollaries of each other. We further suggest that, while the framework of preference aggregation can be mapped into the framework of judgment aggregation, there exists no obvious reverse mapping. Finally, we address one particular minimal condition that is used in both theorems – an independence condition – and suggest that this condition points towards a unifying property underlying both impossibility results. (shrink)

This paper provides an introductory review of the theory of judgment aggregation. It introduces the paradoxes of majority voting that originally motivated the field, explains several key results on the impossibility of propositionwise judgment aggregation, presents a pedagogical proof of one of those results, discusses escape routes from the impossibility and relates judgment aggregation to some other salient aggregation problems, such as preference aggregation, abstract aggregation and probability aggregation. The present illustrative rather than exhaustive review is intended to give readers (...) new to the field of judgment aggregation a sense of this rapidly growing research area. (shrink)

Majority cycling and related social choice paradoxes are often thought to threaten the meaningfulness of democracy. But deliberation can prevent majority cycles – not by inducing unanimity, which is unrealistic, but by bringing preferences closer to single-peakedness. We present the first empirical test of this hypothesis, using data from Deliberative Polls. Comparing preferences before and after deliberation, we find increases in proximity to single-peakedness. The increases are greater for lower versus higher salience issues and for individuals who seem to have (...) deliberated more versus less effectively. They are not merely a byproduct of increased substantive agreement. Our results both refine and support the idea that deliberation, by increasing proximity to single-peakedness, provides an escape from the problem of majority cycling. (shrink)

I model sequential decisions over multiple interconnected propositions and investigate path-dependence in such decisions. The propositions and their interconnections are represented in propositional logic. A sequential decision process is path-dependent if its outcome depends on the order in which the propositions are considered. Assuming that earlier decisions constrain later ones, I prove three main results: First, certain rationality violations by the decision-making agent—individual or group—are necessary and sufficient for path-dependence. Second, under some conditions, path-dependence is unavoidable in decisions made by (...) groups. Third, path-dependence makes decisions vulnerable to strategic agenda setting and strategic voting. I also discuss escape routes from path-dependence. My results are relevant to discussions on collective consistency and reason-based decision-making, focusing not only on outcomes, but also on underlying reasons, beliefs, and constraints. (shrink)

Social choice theory is the study of collective decision processes and procedures. It is not a single theory, but a cluster of models and results concerning the aggregation of individual inputs (e.g., votes, preferences, judgments, welfare) into collective outputs (e.g., collective decisions, preferences, judgments, welfare). Central questions are: How can a group of individuals choose a winning outcome (e.g., policy, electoral candidate) from a given set of options? What are the properties of different voting systems? When is a voting system (...) democratic? How can a collective (e.g., electorate, legislature, collegial court, expert panel, or committee) arrive at coherent collective preferences or judgments on some issues, on the basis of its members' individual preferences or judgments? How can we rank different social alternatives in an order of social welfare? Social choice theorists study these questions not just by looking at examples, but by developing general models and proving theorems. (shrink)

This paper provides an introductory review of the theory of judgment aggregation. It introduces the paradoxes of majority voting that originally motivated the field, explains several key results on the impossibility of propositionwise judgment aggregation, presents a pedagogical proof of one of those results, discusses escape routes from the impossibility and relates judgment aggregation to some other salient aggregation problems, such as preference aggregation, abstract aggregation and probability aggregation. The present illustrative rather than exhaustive review is intended to give readers (...) new to the field of judgment aggregation a sense of this rapidly growing research area. (shrink)