The Pareto principle states that if the members of society express the same preference judgment between two options, this judgment is compelling for society. A building block of normative economics and social choice theory, and often borrowed by contemporary political philosophy, the principle has rarely been subjected to philosophical criticism. The paper objects to it on the ground that it indifferently applies to those cases in which the individuals agree on both their expressed preferences and their reasons for entertaining them, (...) and those cases in which they agree on their expressed preferences, while differing on their reasons. The latter are cases of "spurious unanimity", and it is normatively inappropriate, or so the paper argues, to defend unanimity preservation at the social level for them, so the Pareto principle is formulated much too broadly. The objection seems especially powerful when the principle is applied in an ex ante context of uncertainty, in which individuals can disagree on both their probabilities and utilities, and nonetheless agree on their preferences over prospects. (shrink)

The unanimity theory is an account of property-level causation requiring that causes raise the probability of their effects in specified test situations. Richard Otte (1981) and others have presented counterexamples in which one property is probabilistically sufficient for at least one other property. Given the continuing discussion (e.g., Cartwright 1989; Cartwright and Dupre 1988; Eells 1988a,b), many apparently think that these problems are minor. By considering the impact of Otte's cases on recent versions of the theory, by raising several (...) new examples, and by criticizing natural replies, I argue that the problems for the unanimity theory are severe. (shrink)

Sober and Lewontin's critique of genic selectionism is based upon the principle that a unit of selection should make a context‐independent contribution to fitness. Critics have effectively shown that this principle is flawed. In this paper I show that the context independence principle is an instance of a more general principle for characterizing causes,called the contextual unanimity principle. I argue that this latter principle, while widely accepted, is erroneous. What is needed is to replace the approach to causality characterized (...) by the contextual unanimity criterion with an approach based on the concept of causal mechanism. After sketching such an approach, I show how it can be used to shed light on the units of selection problem. (shrink)

In the context of indivisible public objects problems (e.g., candidate selection or qualification) with “separable” preferences, unanimity rule accepts each object if and only if the object is in everyone’s top set. We establish two axiomatizations of unanimity rule. The main axiom is resource monotonicity, saying that resource increase should affect all agents in the same direction. This axiom is considered in combination with simple Pareto (there is no Pareto improvement by addition or subtraction of a single object), (...) independence of irrelevant alternatives, and either path independence or strategy-proofness. (shrink)

This paper is concerned with the implications of unanimity and anonymity for the Arrovian social choice theory when population is infinite. Contrary to the finite population case, various unanimity and anonymity axioms can be formulated. We show a tension between unanimity and anonymity by providing possibility and impossibility results. We also examine the case in which social preferences are allowed to be quasi-transitive.

Around 97% of climate scientists endorse anthropogenic global warming (AGW), the theory that human activities are partly responsible for recent increases in global average temperatures. Clearly, this widespread endorsement of AGW is a reason for non-experts to believe in AGW. But what is the epistemic significance of the fact that some climate scientists do not endorse AGW? This paper contrasts expert unanimity, in which virtually no expert disagrees with some theory, with expert consensus, in which some non-negligible proportion either (...) rejects or is uncertain about the theory. It is argued that, from a layperson’s point of view, an expert consensus is often stronger evidence for a theory’s truth than unanimity. Several lessons are drawn from this conclusion, e.g. concerning what laypeople should infer from expert pronouncements, how journalists should report on scientific theories, and how working scientists should communicate with the public. (shrink)

One of the issues which arises in connection with the study of mysticism concerns the status of a so-called 'pure consciousness' experience, i.e., a state of consciousness devoid of conceptual or empirical content and often alleged to be characterized by the realization of the mystic's identity with ultimate reality. Proponents of what I shall call the unanimity thesis typically assert that the state of pure consciousness is the common core of all mysticism; variations in accounts of mystical experience result (...) from post-experiential interpretations of this universal state of consciousness which are derived from the conceptual framework of a given mystic's religious tradition. In contrast to the perennialist position are the 'contextualists,' who claim that mystical experience is essentially shaped and constructed by the beliefs and expectations brought to the experience, with the consequence that not only is the very possibility of a state of pure consciousness undermined, but that there are as many varieties of mystical experience as there are traditions which allow for such experiences. ;The present inquiry is concerned with an examination of the state of pure consciousness as mystical experience, and with the often-made distinction between monistic and theistic experience. In this connection, I draw on the Advaita Vedanta philosophy of the eighth century Indian thinker Samkara. I argue that the Vedantic framework provides a justification for claims concerning non-dual, pure consciousness as the ontological ground of reality and as realizable in mystical experience, and sheds light on the monistic/theistic distinction in a way which partially reconciles the perennialist and contextualist positions. ;Despite this partial reconciliation, however, in the final analysis I will suggest that the distinction between monistic and theistic experience is perhaps best understood not in light of a distinction between mystical states of consciousness , but rather in terms of how a mystic approaches the reality he or she believes to be the ultimate source of meaning and value. (shrink)

Given the role consensus is supposed to play in the social aspects of inquiry and deliberation, it is important that we may always identify a consensus as the basis of joint inquiry and deliberation. However, it turns out that if we think of an agent revising her beliefs to reach a consensus, then, on the received view of belief revision, AGM belief revision theory, certain simple and compelling consensus positions are not always available.

This paper considers contractarianism as a method of justification. The analysis accepts the key tenets of contractarianism: expected utility maximization, unanimity as the criteria of acceptance, and social-scientific uncertainty of modelled agents. In addition to these three features, however, the analysis introduces a fourth feature: a criteria of rational belief formation, viz. Bayesian belief updating. Using a formal model, this paper identifies a decisive objection to contractarian justification. Insofar as contractarian projects approximate the Agreement Model, therefore, they fail to (...) justify their conclusions. Insofar as they fail to approximate the Agreement Model, they must explain which modelling assumption they reject. (shrink)

ABSTRACT The notion of consensus plays an important epistemological role in modern welfare economics, in that unanimous consent is a (unique) conceptual test for those changes that are ‘Pareto-desirable’ (that is, make someone better off and no-one else worse). In this paper, we seek to show that unanimous consent does not logically imply Pareto-desirability—that a rational individual may fail to veto policy changes that make him/her worse off. The central element in the proof of this proposition is the observation that (...) in social agreements involving a significant number of participants, any one individual's veto is decisive if it is the only veto. If the individual does not expect to be decisive, he will rationally exercise his vote ‘expressively’, and without sole regard to its consequences. When all individuals so act, a sort of prisoners' dilemma interaction may emerge, even under explicit consensus. (shrink)

The problem of the aggregation of inputs coming from different sources arises in several contexts. Examples are the combination of individual preferences (studied in social choice theory), opinions (judgment aggregation), and data (artificial intelligence). While a number of results are available in each of these disciplines, a question that has been addressed only recently is how similar these aggregation problems are, despite the different types of inputs they try to combine.

The extent of the consensus among scientists on anthropogenic global warming (AGW) has the potential to influence public opinion and the attitude of political leaders and thus matters greatly to society. The history of science demonstrates that if we wish to judge the level of a scientific consensus and whether the consensus position is likely to be correct, the only reliable source is the peer-reviewed literature. During 2013 and 2014, only 4 of 69,406 authors of peer-reviewed articles on global warming, (...) 0.0058% or 1 in 17,352, rejected AGW. Thus, the consensus on AGW among publishing scientists is above 99.99%, verging on unanimity. The U.S. House of Representatives holds 40 times as many global warming rejecters as are found among the authors of scientific articles. The peer-reviewed literature contains no convincing evidence against AGW. (shrink)

This paper presents rational and unanimously agreeable norms in (a) governance, (b) economic policy, (c) constitution and (d) religious and scientific beliefs for civilized coexistence. The basis of unanimous agreeability is that individuals do not prefer to have their wealth (including life) robbed, even surreptitiously. This preference is unanimous because even robbers do not want to be robbed. I argue that unanimously agreeable norms are necessary for civilized co-existence of humans and are consistent with the ancient philosophy (Hindutva), which originated (...) in India more than 3000 years BC and is reflected in Gita, https://en.wikipedia.org/wiki/bhagavad_gita. Gita is considered by Courts of India as a philosophical document. The basic ethos of Gita is explicit and transparent: the state (King Dhristarastra) must not allow anyone (including privileged princes like Duryodhan) to take away others' (Pandavas') property even surreptitiously (through Sakuni's rigged game of Pashakhel). The modern constitution ordains freedom through rights to property, liberty and pursuit for happiness of individuals. But it has tacitly allowed establishment of a system (rules) of governance to facilitate surreptitious robbery. Individuals accumulate property like home and retirement savings with a hope to attain freedom, eventually, which they cannot achieve if they are robbed, even surreptitiously. The ancient philosophy of Gita prohibits robbery of any kind and, thus, guarantees hope for individual freedom. The modern philosophy—underlying the established system (rules) tacitly allowing surreptitious robbery—cannot, however, achieve individual freedom. Widespread or inclusive economic prosperity can be attained only if the constitution and rules of law are unanimously agreeable which will be consistent with ancient ethos but not modern philosophy. (shrink)

This essay is part of a larger project exploring the extent to which the market paradigm might be usefully employed to explain and in some instances justify nonmarket institutions. The focus of the market paradigm in this essay is the relationship between the idea of a perfectly competitive market and aspects of both the rationality of political association and the theory of collective choice. In particular, this essay seeks to identify what connections, if any, exist between one kind of market (...) account of the rationality of political association and one kind of market-based social choice rule. The market theory of political association I intend to discuss I call “market contractarianism,” and the collective choice rule whose relation to it I intend to explore is the unanimity rule. What, if anything, is the relationship between market contractarianism and the unanimity rule? (shrink)

Sober argues that the units of selection problem in evolutionary biology is to be understood and solved by applying the general analysis of what it means for C to cause E in a population. The account he utilizes is the unanimity account, according to which C causes E in a population when C raises the probability of E in each causal context. I argue that he does not succeed here, both because the unanimity account is not well grounded (...) in the general case, and because there are important differences between cases of population causation which do involve selection and those which do not. (shrink)

The units of selection problem is an issue within evolutionary theory (or the philosophy thereof) and concerns the question of what units or objects are acted upon by natural selection -- for example, whether these are genes, organisms or groups of organisms. One of the central theses of Elliot Sober’s recent book, The Nature of Selection, is that the philosophical problem of what it means for something to be a unit of selection is to be understood by applying the correct (...) account of what it is in general for a factor to be a cause in a population.The account of population-causation that Sober utilizes for this purpose comes from the recent literature on probabilistic causality. This account requires that for C to cause E in a population, a unanimity condition must be satisfied: C must raise the probability of E in each causal context. (shrink)

In seeking insight into the intellectual underpinnings of the current “second culture war” and the emphasis on the campus left on speech repression, this chapter turns back to the first culture war of the late 1980s and early 1990s. In particular, it considers the linguistic constructivism put forward by figures such as Richard Rorty, Hans-Georg Gadamer, and Nelson Goodman at the height of postmodernism. This philosophy attributes great power to words, even regarding language as the material out of which reality (...) is built, and it has become almost common coin, especially in various humanities departments. It motivates the control of expression, but that control is only as legitimate as the metaphysics underlying it—the views about truth, reality, and representation—is plausible. Perhaps the turn in philosophy toward realist metaphysics, among other developments, provides a ray of hope in the politically unanimous academy. (shrink)

We examine collective decision-making in a jury voting game under the unanimity rule when voters have ambiguous beliefs. Unlike in existing studies (Ellis in Theoretical Economics 11:865–895, 2016; Fabrizi et al., in: AUT Economics Working Paper, 2021; Ryan in Theory and Decision 90:543–577, 2021), the locus of ambiguity is the likelihood function (signal precision) rather than the prior. This significantly alters the properties of symmetric equilibria. While prior ambiguity may induce multiple equilibria (Fabrizi et al., in: AUT Economics Working (...) Paper, 2021; Ryan in Theory and Decision 90:543–577, 2021) we show that, under likelihood ambiguity, there exists a unique non-trivial symmetric responsive equilibrium that takes the same form as in the absence of ambiguity (Feddersen and Pesendorfer in The American Political Science Review 92:23–35, 1998). Moreover, likelihood ambiguity partially offsets the pernicious effects of pivotality on decision quality: the frequency of Type I error (convicting the innocent) is typically lower than in the absence of ambiguity. (shrink)

Journal of Political Philosophy, EarlyView.

Toward the end of his famous Rule, written late in his life, near the middle of the sixth century, St. Benedict provides instructions for the selection of an abbot, the leader and spiritual "father" of the cenobitic monastic community, who is to represent Christ to the men under his charge. The beginning of Chapter 64 of RB states: In the installation of an abbot, the proper method is always to appoint the one whom the whole community agrees to choose in (...) the fear of God. Or a part of the community, no matter how small, may make the choice if they possess sounder judgment. Let the candidate be chosen for merit of life and wisdom of teaching, even if he hold the last rank in the community. But it can happen... (shrink)

I aim to show how the enigmatic phrase 'Unánime noche' in the famous first sentence of “The Circular Ruins” is inextricably linked to the story’s last words. Toward this purpose, I argue—against plausible foundational interpretations of the story—for a nonfoundational reading of the text and, moreover, that Borges’s use of ‘unánime’ (one soul) can be understood as one character or one form; namely, as an archetype of “Dreamanity” that leads to a vertiginous Third Man regress.

We prove that it is decidable of a finite algebra whether it has a near-unanimity term operation, which settles a ten-year-old problem. As a consequence, it is decidable of a finite algebra in a congruence distributive variety whether it admits a natural duality.

We investigate the conflict between the ex ante and ex post criteria of social welfare in a new framework of individual and social decisions, which distinguishes between two sources of uncertainty, here interpreted as an objective and a subjective source respectively. This framework makes it possible to endow the individuals and society not only with ex ante and ex post preferences, as is usually done, but also with interim preferences of two kinds, and correspondingly, to introduce interim forms of the (...) Pareto principle. After characterizing the ex ante and ex post criteria, we present a first solution to their conflict that extends the former as much possible in the direction of the latter. Then, we present a second solution, which goes in the opposite direction, and is also maximally assertive. Both solutions translate the assumed Pareto conditions into weighted additive utility representations, and both attribute to the individuals common probability values on the objective source of uncertainty, and different probability values on the subjective source. We discuss these solutions in terms of two conceptual arguments, i.e., the by now classic spurious unanimity argument and a novel informational argument labelled complementary ignorance. The paper complies with the standard economic methodology of basing probability and utility representations on preference axioms, but for the sake of completeness, also considers a construal of objective uncertainty based on the assumption of an exogeneously given probability measure. JEL classification: D70; D81. (shrink)

While many of us would not want to abandon the requirement that a defendant can only be found guilty of a serious criminal offence by a unanimous jury, we should not expect epistemology to give us the resources we need for justifying this requirement. The doubts that might prevent jurors from reaching unanimity do not show that, say, the BARD standard has not been met. Even if it were true, as some have suggested, that rationality requires that a jury (...) composed of epistemic peers should coalesce around one view about the defendant’s guilt, the failure to reach unanimity might be a good reason to worry about the epistemic failings of some small number of jurors but no reason to worry that we’ve failed to protect the defendant from an unjustified imposition of, say, the risk against wrongful conviction. The arguments for the unanimity requirement will need to come from outside of epistemology. (shrink)

In his plea for consensual democracy in Africa, Kwasi Wiredu recommends unanimity about what is to be done, not what ought to be done, or unanimity on action rather than unanimity of values, beliefs and opinion. I caution the use of this procedural instrument by showing that some issues are so value-laden that a group decision cannot be value-neutral. It may sometimes be more productive to entertain value differences to keep them from going underground and becoming dangerous. (...) However, the ability to locate some common interest or ground seems to be crucial for such value confrontation. (shrink)

There have been two parallel views regarding the role of voting in deliberation. The first is that deliberation before the fabrication of balloting was completely devoid of voting. The second is that voting is, not just part of deliberation, but is standard to deliberation. I argue in this article that neither of these views is correct. Implicit voting has always existed across time and space but only as a last resort in the event of a failure of natural unanimity. (...) What is relatively modern is the establishment of what I call explicit voting, namely, balloting, outside deliberation and often without deliberation. I also distinguish between natural and artificial unanimities, and clarify that artificial unanimities are products of implicit voting. I demonstrate these clarifications with some examples of deliberation. I deploy these clarifications to rid a certain debate of confusion regarding the precise role of voting in consensual deliberation. (shrink)

We address Northcott’s criticism of Pearson’s correlation coefficient ‘r’ in measuring causal strength by replacing Pearson’s linear regressions by nonparametric nonlinear kernel regressions. Although new proof shows that Suppes’ intuitive causality condition is neither necessary nor sufficient, we resurrect Suppes’ probabilistic causality theory by using nonlinear tools. We use asymmetric generalized partial correlation coefficients from Vinod [2014] as our third criterion in addition to two more criteria. We aggregate the three criteria into one unanimity index, UI in [-100; 100], (...) quantifying causal strengths associated with causal paths: Xi -> Xj, Xj -> Xi, and Xi Xj. (shrink)

A dichotomous decision-making context in committees is considered where potential partisan members with predetermined votes can generate inefficient decisions and buy neutral votes. The optimal voting rule minimizing the expected costs of inefficient decisions for the case of a three-member committee is analyzed. It is shown that the optimal voting rule can be non-monotonic with respect to side-transfers: in the symmetric case, majority voting is optimal under either zero, mild or full side-transfer possibilities, whereas unanimity voting may be optimal (...) under an intermediate side-transfer possibility. The side-transfer possibilities depend on the power of partisans (their ability or willingness to pay for neutral votes) relative to the corruptibility of neutral members (personal cost of deliberately casting a `wrong' vote). (shrink)

When preferences are defined over two alternatives and societies are variable, the group formed by the relative majority rule, the unanimity rule, the dictatorial rules, and the strongly dictatorial rules is characterized in terms of five axioms: unanimity, reducibility, substitutability, exchangeability, and parity. This result is used to provide characterizations of each of these rules by postulating separating axioms, that is, an axiom and its negation. Such axioms identify traits specifically differentiating a type of rule from the other (...) types. For instance, majority differs from strong dictatorship in the existence of a society for which collective indifference should be a less likely outcome than the strict preference of one alternative over the other. As a second example, the difference between majority and strong dictatorship can be traced back to the requirement that the likelihood of collective indifference diminishes with the size of society. (shrink)