The Uniqueness Thesis holds, roughly speaking, that there is a unique rational response to any particular body of evidence. We first sketch some varieties of Uniqueness that appear in the literature. We then discuss some popular views that conflict with Uniqueness and others that require Uniqueness to be true. We then examine some arguments that have been presented in its favor and discuss why permissivists find them unconvincing. Last, we present some purported counterexamples that have been (...) raised against Uniqueness and discuss some possible reasons why proponents of Uniqueness might find these similarly unconvincing. (shrink)

We defend Uniqueness, the claim that given a body of total evidence, there is a uniquely rational doxastic state that it is rational for one to be in. Epistemic rationality doesn't give you any leeway in forming your beliefs. To this end, we bring in two metaepistemological pictures about the roles played by rational evaluations. Rational evaluative terms serve to guide our practices of deference to the opinions of others, and also to help us formulate contingency plans about what (...) to believe in various situations. We argue that Uniqueness vindicates these two roles for rational evaluations, while Permissivism clashes with them. (shrink)

Conciliationism holds that disagreement of apparent epistemic peers often substantially undermines rational confidence in our opinions. Uniqueness principles say that there is at most one maximally rational doxastic response to any given batch of total evidence. The two views are often thought to be tightly connected. This paper distinguishes two ways of motivating conciliationism, and two ways that conciliationism may be undermined by permissive accounts of rationality. It shows how conciliationism can flourish under certain strongly permissive accounts of rationality. (...) This occurs when the motivation for conciliationism does not come from taking disagreement as evidence of one's own rational failings. However, divorcing the motive for conciliating from worries about rationality does not remove a feature of conciliationism that some find troubling: that conciliationism can lead to cases of “rational toxicity,” in which the most rational response to one's evidence involves violating some rational ideal. (shrink)

Two theses figure centrally in work on the epistemology of disagreement: Equal Weight (‘EW’) and Uniqueness (‘U’). According to EW, you should give precisely as much weight to the attitude of a disagreeing epistemic peer as you give to your own attitude. U has it that, for any given proposition and total body of evidence, some doxastic attitude is the one the evidence makes rational (justifies) toward that proposition. Although EW has received considerable discussion, the case for U has (...) not been critically evaluated. Endorsing U, we argue, commits one to the highly controversial thesis that whatever fixes your rational attitudes can do so only by fixing what evidence you have. This commitment imposes a relatively demanding requirement on justified belief in U, one that we argue is not satisfied by what is currently the strongest available case for U, due to Roger White [2005]. Our challenge to U makes more trouble for its proponents than do the worries about U expressed by Gideon Rosen [2001] and Thomas Kelly [2010]. Moreover, if Kelly [2010] is correct in thinking that EW “carries with it a commitment to” U—a claim which we accept for reasons similar to Kelly’s but is beyond this paper’s scope (but see Ballantyne and Coffman [forthcoming])—then our challenge to U bears importantly on EW: to the extent that our challenge to U succeeds, EW also suffers. (shrink)

It is widely agreed that hypocrisy can undermine one’s moral standing to blame. According to the Nonhypocrisy Condition on standing, R has the standing to blame some other agent S for a violation of some norm N only if R is not hypocritical with respect to blame for violations of N. Yet this condition is seldom argued for. Macalester Bell points out that the fact that hypocrisy is a moral fault does not yet explain why hypocritical blame is standingless blame. (...) She raises a challenge: one must explain what is distinct about hypocritical blame such that the hypocritical blamer lacks the standing to blame, even if the arrogant or petty blamer does not. Of those writing on hypocrisy, only we offer a direct response to Bell’s challenge. Recently, however, our account has come under criticism. We argue here that (1) our account can handle these criticisms and that (2) no other rival account adequately addresses Bell’s challenge of explaining what is uniquely objectionable about hypocritical blame. Because answering Bell’s challenge is a necessary component of any plausible account of the relationship between hypocrisy and standing, our account remains the best on offer. (shrink)

By taking the practical relevance of coordinated epistemic standards into account, Dogramaci and Horowitz (2016) as well as Greco and Hedden (2016) offer a new perspective on epistemic permissiveness. However, in its current state, their argument appears to be inconclusive. I will offer two reasons why this argument does not support interpersonal uniqueness in general. First, such an argument leaves open the possibility that distinct closed societies come to incompatible epistemic standards. Second, some epistemic practices like the promotion of (...) methodological heterogeneity in epistemic communities could be best explained by epistemic permissiveness. (shrink)

White, Christensen, and Feldman have recently endorsed uniqueness, the thesis that given the same total evidence, two rational subjects cannot hold different views. Kelly, Schoenfield, and Meacham argue that White and others have at best only supported the weaker, merely intrapersonal view that, given the total evidence, there are no two views which a single rational agent could take. Here, we give a new argument for uniqueness, an argument with deliberate focus on the interpersonal element of the thesis. (...) Our argument is that the best explanation of the value of promoting rationality is an explanation that entails uniqueness. (shrink)

Reading systematically activates the left lateral occipitotemporal sulcus, at a site known as the visual word form area (VWFA). This site is reproducible across individuals/scripts, attuned to reading-specific processes, and partially selective for written strings relative to other categories such as line drawings. Lesions affecting the VWFA cause pure alexia, a selective deficit in word recognition. These findings must be reconciled with the fact that human genome evolution cannot have been influenced by such a recent and culturally variable activity as (...) reading. Capitalizing on recent functional magnetic resonance imaging experiments, we provide strong corroborating evidence for the hypothesis that reading acquisition partially recycles a cortical territory evolved for object and face recognition, the prior properties of which influenced the form of writing systems. (shrink)

Most people would agree that adoption is a good thing for children in need of a family. Yet adoption is often considered a second best or even last resort for parents in making their families. Against this assumption, I explore the unique value of adoption for prospective parents. I begin with a criticism of the selective focus on the value of adoption for only those people using assisted reproductive technologies. I focus on the value of adoption for all prospective parents, (...) reflecting on non-relative, non-procreative adoptions. First, adoption can meet the important need that a child has for a family, whereas procreation creates rather than meets needs. Second, adoption provides a morally noble opportunity to extend to a stranger benefits usually withheld for one's genetic kin. As such, adoption offers a unique possibility in which impartial concern for an other can be the starting point for a lifetime of love and care. Finally, adoptions can have transformative power over adoptive parents’ conception of family and self. In highlighting the unique value of adoption, I aim to challenge the widespread assumption that adoption has second best status to procreation. Indeed adoption can exemplify the human potential for moral compassion and impartial concern for the needs of others. (shrink)

A comparison is given between two conditions used to define logical constants: Belnap's uniqueness and Hacking's deducibility of identicals. It is shown that, in spite of some surface similarities, there is a deep difference between them. On the one hand, deducibility of identicals turns out to be a weaker and less demanding condition than uniqueness. On the other hand, deducibility of identicals is shown to be more faithful to the inferentialist perspective, permitting definition of genuinely proof-theoretical concepts. This (...) kind of analysis is driven by exploiting the Curry–Howard correspondence. In particular, deducibility of identicals is shown to correspond to the computational property of eta expansion, which is essential in the characterization of propositional identity. (shrink)

The purpose of this essay is to determinewhat exactly is meant by the claimcomputer ethics is unique, a position thatwill henceforth be referred to as the CEIUthesis. A brief sketch of the CEIU debate is provided,and an empirical case involving a recentincident of cyberstalking is briefly consideredin order to illustrate some controversialpoints of contention in that debate. To gain aclearer understanding of what exactly isasserted in the various claims about theuniqueness of computer ethics, and to avoidmany of the confusions currently (...) associatedwith the term ``unique'', a precise definition ofthat term is proposed. We then differentiatetwo distinct and radically differentinterpretations of the CEIU thesis, based onarguments that can be found in the relevantcomputer ethics literature. The twointerpretations are critically analyzed andboth are shown to be inadequate in establishingthe CEIU thesis. We then examine and reject twoassumptions implicit in arguments advanced bothby CEIU advocates and their opponents. Inexposing and rejecting these assumptions, wesee why it is not necessary to accept theconclusions reached by either side in thisdebate. Finally, we defend the view thatcomputer ethics issues are both philosophicallyinteresting and deserving of our attention,regardless of whether those issues might alsohappen to be unique ethical issues. (shrink)

We prove a uniqueness theorem showing that, subject to certain natural constraints, all 'no collapse' interpretations of quantum mechanics can be uniquely characterized and reduced to the choice of a particular preferred observable as determine (definite, sharp). We show how certain versions of the modal interpretation, Bohm's 'causal' interpretation, Bohr's complementarity interpretation, and the orthodox (Dirac-von Neumann) interpretation without the projection postulate can be recovered from the theorem. Bohr's complementarity and Einstein's realism appear as two quite different proposals for (...) selecting the preferred determinate observable--either settled pragmatically by what we choose to observe, or fixed once and for all, as the Einsteinian realist would require, in which case the preferred observable is a 'beable' in Bell's sense, as in Bohm's interpretation (where the preferred observable is position in configuration space). (shrink)

I present an argument against the thesis of Uniqueness and in favour of Permissivism. Counterexamples to Uniqueness are provided, based on ‘Safespot’ propositions – i.e. a proposition that is guaranteed to be true provided the subject adopts a certain attitude towards it. The argument relies on a plausible principle: (roughly stated) If S knows that her believing p would be a true belief, then it is rationally permitted for S to believe p. One motivation for denying this principle (...) – viz. opposition to ‘epistemic consequentialism’ – is briefly discussed. The principle is extended to cover degrees of belief and compared with a couple of other well-known constraints on rational degrees of belief. (shrink)

The A-theory and the B-theory advance competing claims about how time is grounded. The A-theory says that A-facts are more fundamental in grounding time than are B-facts, and the B-theory says the reverse. We argue that whichever theory is true of the actual world is also true of all possible worlds containing time. We do this by arguing that time is uniquely groundable: however time is actually grounded, it is necessarily grounded in that way. It follows that if either the (...) A-theory or the B-theory is actually false, then it is necessarily false. (shrink)

The A-theory and the B-theory advance competing claims about how time is grounded. The A-theory says that A-facts are more fundamental in grounding time than are B-facts, and the B-theory says the reverse. We argue that whichever theory is true of the actual world is also true of all possible worlds containing time. We do this by arguing that time is uniquely groundable: however time is actually grounded, it is necessarily grounded in that way. It follows that if either the (...) A-theory or the B-theory is actually false, then it is necessarily false. (shrink)

Deference principles are principles that describe when, and to what extent, it’s rational to defer to others. Recently, some authors have used such principles to argue for Evidential Uniqueness, the claim that for every batch of evidence, there’s a unique doxastic state that it’s permissible for subjects with that total evidence to have. This paper has two aims. The first aim is to assess these deference-based arguments for Evidential Uniqueness. I’ll show that these arguments only work given a (...) particular kind of deference principle, and I’ll argue that there are reasons to reject these kinds of principles. The second aim of this paper is to spell out what a plausible generalized deference principle looks like. I’ll start by offering a principled rationale for taking deference to constrain rational belief. Then I’ll flesh out the kind of deference principle suggested by this rationale. Finally, I’ll show that this principle is both more plausible and more general than the principles used in the deference-based arguments for Evidential Uniqueness. (shrink)

Cet ouvrage parut d'abord en anglais, aux Etats-Unis, sous le titre The Work of Mourning. Pascale-Anne Brault et Michael Naas, Professeurs à l'université DePaul, à Chicago, en eurent l'initiative. Ils ont ainsi présenté et traduit tous les textes que Jacques Derrida aura publiés, au cours des vingt dernières années, en Europe ou aux Etats-Unis, à la mort de certains de ses amis qui furent aussi, dans l'espace public, des écrivains, des philosophes, des professeurs : Roland Barthes, Paul de Man, Michel (...) Foucault, Max Loreau, Jean-Marie Benoist, Louis Althusser, Edmond Jabès, Joseph N. Riddel, Michel Servière, Louis Marin, Sarah Kofman, Gilles Deleuze, Emmanuel Lévinas, Jean-François Lyotard, Gérard Granel, Maurice Blanchot. Le tristesse de ces réflexions est chaque fois vouée et dévouée à la mort de l'irremplaçable. Mais bien que de telles " adresses " soient ainsi tourmentées, dans leur destination même, par cette pensée de la fidélité à l'unique ou du deuil impossible, elles restent comme " enchaînées ". Enchaînées entre elles, tenues à leur signature commune, inévitablement. Une analogie sans répétition s'y fait donc insistante. Excédant chaque fois tout " travail du deuil ", mettant la pensée au travail sur ce que signifie l'échec dudit " travail du deuil ", elle contresigne l'engagement sans fin auprès de l'ami mort. C'est cette étrange " logique ", ce sont ces apories que Pascale-Anne Brault et Michael Naas analysent dans une longue et admirable introduction. Celle-ci ne reconstitue pas seulement, pour l'éclairer de façon inédite, tout un réseau de textes consacrés par Derrida à la mort et au deuil. Brault et Naas élaborent à leur compte, de façon fort originale, la question d'une " politique du deuil ". De précieuses biographies et bibliographies ont été mises au point par Kas Saghafi. L'ouvrage comporte enfin, dans cette édition française, un avant-propos de Jacques Derrida. (shrink)

ABSTRACT Living well in the 21st century will present human beings with a unique set of demands and ethical challenges, many of which will require a rapid response to developments in the online space. Online activities increasingly permeate our practical lives. Although there is every indication that this activity will intensify, even experts on digital technology recognise that the precise effects of future emergent technology will be uncertain and remain unknown. We argue that education directed at the cultivation of cyber-wisdom (...) and other cyber-virtues provides our best chance of creating a moral vocabulary that can guide us towards living well in the 21st century. The aim of this article is to offer the first outline of an educational model, founded on neo-Aristotelian theory, that illustrates how these qualities could be cultivated through moral education. (shrink)

The Uniqueness Thesis, or rational uniqueness, claims that a body of evidence severely constrains one’s doxastic options. In particular, it claims that for any body of evidence E and proposition P, E justifies at most one doxastic attitude toward P. In this paper I defend this formulation of the uniqueness thesis and examine the case for its truth. I begin by clarifying my formulation of the Uniqueness Thesis and examining its close relationship to evidentialism. I proceed (...) to give some motivation for this strong epistemic claim and to defend it from several recent objections in the literature. In particular I look at objections to the Uniqueness Thesis coming from considerations of rational disagreement (can’t reasonable people disagree?), the breadth of doxastic attitudes(can’t what is justified by the evidence encompass more than one doxastic attitude?), borderline cases and caution (can’t it be rational to be cautious and suspend judgment even when the evidence slightly supports belief?), vagueness (doesn’t the vagueness of justification spell trouble for the Uniqueness Thesis?), and degrees of belief (doesn’t a finegrained doxastic picture present additional problems for the Uniqueness Thesis?). (shrink)

Pascal Engel (2008) has insisted that a number of notable strategies for rejecting the knowledge norm of assertion are put forward on the basis of the wrong kinds of reasons. A central aim of this paper will be to establish the contrast point: I argue that one very familiar strategy for defending the knowledge norm of assertion—viz., that it is claimed to do better in various respects than its competitors (e.g. the justification and the truth norms)— relies on a presupposition (...) that is shown to be ultimately under motivated. That presupposition is the uniqueness thesis—that there is a unique epistemic rule for assertion, and that such a rule will govern assertions uniformly. In particular, the strategy I shall take here will be to challenge the sufficiency leg of the knowledge norm in a way that at the same time counts against Williamson’s (2000) own rationale for the uniqueness thesis. However, rather than to challenge the sufficiency leg of the knowledge norm via the familiar style of ‘expert opinion’ and, more generally, ‘second-hand knowledge’ cases (e.g. Lackey (2008)), a strategy that has recently been called into question by Benton (2014), I’ll instead advance a very different line of argument against the sufficiency thesis, one which turns on a phenomenon I call epistemic hypocrisy. (shrink)

Various authors have recently argued that you cannot rationally stick to your belief in the face of known disagreement with an epistemic peer, that is, a person you take to have the same evidence and judgmental skills as you do. For, they claim, because there is but one rational response to any body of evidence, a disagreement with an epistemic peer indicates that at least one of you is not responding rationally to the evidence. Given that you take your peer (...) to have the same judgmental skills as you do, and thus regard her to be equally good at assessing the evidence as you are, you will have as much reason for thinking that it is you who is not responding rationally to the evidence as for thinking that it is her. You thus have reason for thinking that your belief on the disputed matter is not a rational response to the evidence. Hence, you cannot rationally stick to your belief. (shrink)

A response is given here to Benacerraf's (1965) non-uniqueness (or multiple-reductions) objection to mathematical platonism. It is argued that non-uniqueness is simply not a problem for platonism; more specifically, it is argued that platonists can simply embrace non-uniqueness—i.e., that one can endorse the thesis that our mathematical theories truly describe collections of abstract mathematical objects while rejecting the thesis that such theories truly describe unique collections of such objects. I also argue that part of the motivation for (...) this stance is that it dovetails with the correct response to Benacerraf's other objection to platonism, i.e., his (1973) epistemological objection. (shrink)

A distinction is made between moral indoctrination and instruction in ethics. It is argued that the legitimate and important field of computer ethics should not be permitted to become mere moral indoctrination. Computer ethics is an academic field in its own right with unique ethical issues that would not have existed if computer technology had not been invented. Several example issues are presented to illustrate this point. The failure to find satisfactory non-computer analogies testifies to the uniqueness of computer (...) ethics. Lack of an effective analogy forces us to discover new moral values, formulate new moral principles, develop new policies, and find new ways to think about the issues presented to us. For all of these reasons, the kind of issues presented deserve to be addressed separately from others that might at first appear similar. At the very least, they have been so transformed by computing technology that their altered form demands special attention. (shrink)

Saunders & van Brakel argue, inter alia, that there is for the claim that there are four unique hues (red, green, blue, and yellow), and that there are two corresponding opponent processes. We argue that this is quite mistaken.

In this essay, I present a straightforward counterexample to the Uniqueness Thesis, which holds, roughly speaking, that there is a unique rational response to any particular body of evidence.

The paper explicates unique events and investigates their epistemology. Explications of unique events as individuated, different, and emergent are philosophically uninteresting. Unique events are topics of why-questions that radically underdetermine all their potential explanations. Uniqueness that is relative to a level of scientific development is differentiated from absolute uniqueness. Science eliminates relative uniqueness by discovery of recurrence of events and properties, falsification of assumptions of why-questions, and methodological simplification e.g. by explanatory methodological reduction. Finally, an overview of (...) contemporary philosophical disputes that hinge on issues of uniqueness emphasizes its philosophical significance. (shrink)

For contractarians, justice is the result of a rational bargain. The goal is to show that the rules of justice are consistent with rationality. The two most important bargaining theories of justice are David Gauthier’s and those that use the Nash’s bargaining solution. I argue that both of these approaches are fatally undermined by their reliance on a symmetry condition. Symmetry is a substantive constraint, not an implication of rationality. I argue that using symmetry to generate uniqueness undermines the (...) goal of bargaining theories of justice. (shrink)

Persons are thought to have a special kind of value, often called "dignity," which, according to Kant, makes them both infinitely valuable and irreplaceably valuable. The author aims to identify what makes a person a person in a way that can explain both aspects of dignity. She considers five definitions of "person": (1) an individual substance of a rational nature (Boethius), (2) a self-conscious being (Locke), (3) a being with the capacity to act for ends (Kant), (4) a being with (...) the capacity to act for another (Kant), and (5) an incommunicably unique subject (Wojtyla). She argues that none is capable of grounding both aspects of dignity since they are incompatible kinds of value; it is impossible for the same thing to ground both. Human persons are infinitely valuable in virtue of shareable qualities of their nature, whereas they are irreplaceably valuable because of a nonqualitative feature of their personhood. (shrink)

Abstract. The concept of human uniqueness has long played a central role within key interpretations of the hominid fossil record and within numerous theological understandings of the imago Dei. More recently, the status of humans as evolutionarily unique has come under strong criticism owing to the discovery of certain nonhuman hominids who, as language and culture-bearing beings, lived as contemporaries with early anatomically modern humans. Nevertheless, many scholars, including those in the field of religion and science, continue to interpret (...) the remains of these other hominids in light of empirically ungrounded implicit assumptions about human uniqueness, which the author calls “anthropocentrism of the gaps.” This paper argues that “anthropocentrism of the gaps” is philosophically unwarranted and thus should not be assumed by scholars in religion and science when evaluating contemporary findings in paleoanthropology. (shrink)

This paper discusses the uniqueness thesis, a core thesis in the epistemology of disagreement. After presenting uniqueness and clarifying relevant terms, a novel counterexample to the thesis will be introduced. This counterexample involves logical disagreement. Several objections to the counterexample are then considered, and it is argued that the best responses to the counterexample all undermine the initial motivation for uniqueness.

In this paper, I offer two counterexamples to the so-called ‘Uniqueness Thesis.’ As one of these examples rely on the thesis that it is possible for a justified belief to be based on an inconsistent body of evidence, I also offer reasons for this further thesis. On the assumption that doxastic justification entails propositional justification, the counterexamples seem to work.

It is folklore that if a continuous function on a complete metric space has approximate roots and in a uniform manner at most one root, then it actually has a root, which of course is uniquely determined. Also in Bishop's constructive mathematics with countable choice, the general setting of the present note, there is a simple method to validate this heuristic principle. The unique solution even becomes a continuous function in the parameters by a mild modification of the uniqueness (...) hypothesis. Moreover, Brouwer's fan theorem for decidable bars turns out to be equivalent to the statement that, for uniformly continuous functions on a compact metric space, the crucial uniform “at most one” condition follows from its non-uniform counterpart. This classification in the spirit of the constructive reverse mathematics, as propagated by Ishihara and others, sharpens an earlier result obtained jointly with Berger and Bridges. (shrink)

I argue that an evolutionary adaptation for bodily mimesis, the volitional use of the body as a representational devise, is the “small difference” that gave rise to unique and yet pre-linguistic features of humanity such as imitation, pedagogy, intentional communication and the possibility of a cumulative, representational culture. Furthermore, it is this that made the evolution of language possible. In support for the thesis that speech evolved atop bodily mimesis and a transitional multimodal protolanguage, I review evidence for the extensive (...) presence of sound-symbolism in modern languages, for its psychological reality in adults, and for its contribution to language acquisition in children. On a meta-level, the argument is that dividing human cognitive-semiotic evolution into a sequence of stages is crucial for resolving classical dichotomies concerning human nature and language, which are both natural and cultural, both continuous with and discontinuous from those of animals. (shrink)

A distinction is made between moral indoctrination and instruction in ethics. It is argued that the legitimate and important field of computer ethics should not be permitted to become mere moral indoctrination. Computer ethics is an academic field in its own right with unique ethical issues that would not have existed if computer technology had not been invented. Several example issues are presented to illustrate this point. The failure to find satisfactory non-computer analogies testifies to the uniqueness of computer (...) ethics. Lack of an effective analogy forces us to discover new moral values, formulate new moral principles, develop new policies, and find new ways to think about the issues presented to us. For all of these reasons, the kind of issues presented deserve to be addressed separately from others that might at first appear similar. At the very least, they have been so transformed by computing technology that their altered form demands special attention. (shrink)

This collection of revised and new essays argues that biology is an autonomous science rather than a branch of the physical sciences. Ernst Mayr, widely considered the most eminent evolutionary biologist of the 20th century, offers insights on the history of evolutionary thought, critiques the conditions of philosophy to the science of biology, and comments on several of the major developments in evolutionary theory. Notably, Mayr explains that Darwin's theory of evolution is actually five separate theories, each with its own (...) history, trajectory and impact. Ernst Mayr, commonly referred to as the "Darwin of the 20th century" and listed as one of the top 100 scientists of all-time, is Professor Emeritus at Harvard University. What Makes Biology Unique is the 25th book he has written during his long and prolific career. His recent books include This is Biology: The Science of the Living World (Belknap Press, 1997) and What Evolution Is (Basic Books, 2002). (shrink)

Two theses are central to recent work on the epistemology of disagreement: Conciliationism:?In a revealed peer disagreement over P, each thinker should give at least some weight to her peer's attitude. Uniqueness:?For any given proposition and total body of evidence, the evidence fully justifies exactly one level of confidence in the proposition. 1This paper is the product of full and equal collaboration between its authors. Does Conciliationism commit one to Uniqueness? Thomas Kelly 2010 has argued that it does. (...) After some scene-setting (?1), in ?2 we explain and criticize Kelly's argument, thereby defeating his larger argument that Conciliationism deserves no dialectical special treatment. But we argue further that Conciliationists are committed to a disjunction, one of whose disjuncts is Uniqueness, that amounts to an ?extremely strong and unobvious position? (??3?4). If we are correct, theorists should not treat Conciliationism as a default position in debates about the epistemic significance of disagreement. (shrink)

It is well known that, in Peano arithmetic, there exists a formula Theor (x) which numerates the set of theorems. By Gödel's and Löb's results, we have that Theor (˹p˺) ≡ p implies p is a theorem ∼Theor (˹p˺) ≡ p implies p is provably equivalent to Theor (˹0 = 1˺). Therefore, the considered "equations" admit, up to provable equivalence, only one solution. In this paper we prove (Corollary 1) that, in general, if P (x) is an arbitrary formula built (...) from Theor (x), then the fixed-point of P (x) (which exists by the diagonalization lemma) is unique up to provable equivalence. This result is settled referring to the concept of diagonalizable algebra (see Introduction). (shrink)

Wentzel van Huyssteen's Gifford Lectures, published as Alone in the World? Human Uniqueness in Science and Theology, accomplish critical and constructive thinking about interdisciplinary reflection on science and religion and about the meaning of human uniqueness. One approach to discussion of van Huyssteen's text entails consideration of three issues: the contextual character of research on humans and animals, the difficult problem of defining uniqueness, and the important consequences of exploring human uniqueness. Evolutionary biology and primatology contribute (...) specific scientific insights. (shrink)

I argue that it is epistemically permissible to believe that P when it is epistemically rational to believe that P. Unlike previous defenses of this claim, this argument is not vulnerable to the claim that permissibility is being confused with excusability.

There is a divide in epistemology between those who think that, for any hypothesis and set of total evidence, there is a unique rational credence in that hypothesis, and those who think that there can be many rational credences. Schultheis offers a novel and potentially devastating objection to Permissivism, on the grounds that Permissivism permits dominated credences. I will argue that Permissivists can plausibly block Schultheis' argument. The issue turns on getting clear about whether we should be certain whether our (...) credences are rational. (shrink)

We consider the problem of uniqueness of certain simultaneity structures in flat spacetime. Absolute simultaneity is specifiled to be a non-trivial equivalence relation which is invariant under the automorphism group Aut of spacetime. Aut is taken to be the identity-component of either the inhomogeneous Galilei group or the inhomogeneous Lorentz group. Uniqueness of standard simultaneity in the first, and absence of any absolute simultaneity in the second case are demonstrated and related to certain group theoretic properties. Relative simultaneity (...) with respect to an additional structure X on spacetime is specified to be a non-trivial equivalence relation which is invariant under the subgroup in Aut that stabilises X. Uniqueness of standard Einstein simultaneity is proven in the Lorentzian case when X is an inertial frame. We end by discussing the relation to previous work of others. (shrink)

This essay begins with a consideration of one way in which animals and persons may be valued as “irreplaceable.” Drawing on both Plato and Pascal, I consider reasons for skepticism regarding the legitimacy of this sort of attachment. While I do not offer a complete defense against such skepticism, I do show that worries here may be overblown due to the conflation of distinct metaphysical and normative concerns. I then go on to clarify what sort of value is at issue (...) in cases of irreplaceable attachment. I characterize “unique value” as the kind of value attributed to a thing when we take that thing to be (theoretically, not just practically) irreplaceable. I then consider the relationship between this sort of value and intrinsic value. After considering the positions of Gowans, Moore, Korsgaard, Frankfurt, and others, I conclude that unique value is best understood not as a variety of intrinsic value but rather as one kind of final value that is grounded in the extrinsic properties of the object. (shrink)

I defend Conciliationism: rationality requires belief revision of epistemic peers who find themselves in disagreement and lack dispute-independent reason to suspect each other of error. (Kelly 2010) argues that Conciliationists are committed to the Uniqueness Thesis: a given body of evidence rationalizes a unique degree of confidence for a given proposition. (Ballantyne & Coffman 2012) cogently critique Kelly's argument and propose an improved version. I contend that their version of the argument is unsound, and I offer some friendly amendments. (...) But I show that even this amended argument threatens only extreme versions of Conciliationism. (shrink)