While we are commonly told that the distinctive method of mathematics is rigorous proof, and that the special topic of mathematics is abstract structure, there has been no agreement among mathematicians, logicians, or philosophers as to just what either of these assertions means. John P. Burgess clarifies the nature of mathematical rigor and of mathematical structure, and above all of the relation between the two, taking into account some of the latest developments in mathematics, including the rise of experimental mathematics (...) on the one hand and computerized formal proofs on the other hand. Along the way, a great many historical developments in mathematics, philosophy, and logic are surveyed. Yet very little in the way of background knowledge on the part of the reader is presupposed. (shrink)

Mathematical proof is the primary form of justification for mathematical knowledge, but in order to count as a proper justification for a piece of mathematical knowl- edge, a mathematical proof must be rigorous. What does it mean then for a mathematical proof to be rigorous? According to what I shall call the standard view, a mathematical proof is rigorous if and only if it can be routinely translated into a formal proof. The standard view is almost an orthodoxy among contemporary (...) mathematicians, and is endorsed by many logicians and philosophers, but it has also been heavily criticized in the philosophy of mathematics literature. Progress on the debate between the proponents and opponents of the standard view is, however, currently blocked by a major obstacle, namely the absence of a precise formulation of it. To remedy this deficiency, I undertake in this paper to provide a precise formulation and a thorough evaluation of the standard view of mathematical rigor. The upshot of this study is that the standard view is more robust to criticisms than it transpires from the various arguments advanced against it, but that it also requires a certain conception of how mathematical proofs are judged to be rigorous in mathematical practice, a conception that can be challenged on empirical grounds by exhibiting rigor judgments of mathematical proofs in mathematical practice conflicting with it. (shrink)

Criteria of acceptability for mathematical proofs are field-dependent. In topology, though not in most other domains, it is sometimes acceptable to appeal to visual intuition to support inferential steps. In previous work :829–842, 2014; Lolli, Panza, Venturi From logic to practice, Springer, Berlin, 2015; Larvor Mathematical cultures, Springer, Berlin, 2016) my co-author and I aimed at spelling out how topological proofs work on their own terms, without appealing to formal proofs which might be associated with them. In this article, I (...) address two criticisms that have been raised in Tatton-Brown against our approach: that it leads to a form of relativism according to which validity is equated with social agreement and that it implies an antiformalizability thesis according to which it is not the case that all rigorous mathematical proofs can be formalized. I reject both criticisms and suggest that our previous case studies provide insight into the plausibility of two related but quite different theses. (shrink)

Rigorous proof is supposed to guarantee that the premises invoked imply the conclusion reached, and the problem of rigor may be described as that of bringing together the perspectives of formal logic and mathematical practice on how this is to be achieved. This problem has recently raised a lot of discussion among philosophers of mathematics. We survey some possible solutions and argue that failure to understand its terms properly has led to misunderstandings in the literature.

A proof is given that there does not exist an event, that is not already in the past for some possible distant observer at the (our) moment that the latter is "now" for us. Such event is as "legally" past for that distant observer as is the moment five minutes ago on the sun for us (irrespective of the circumstance that the light of the sun cannot reach us in a period of five minutes). Only an extreme positivism: "that which (...) cannot yet be observed does not yet exist", can possibly withstand the conclusion concerned. Therefore, there is determinism, also in micro-physics. (shrink)

In his seminars on the death penalty, Derrida consistently describes Kant's arguments in favor of capital punishment as “rigorous” and explicitly relates that rigor to the mechanisms of execution and the subsequent rigor mortis of the corpse. ‘Rigor’ has also often been a contested term in descriptions of deconstruction: different commentators have either deplored or celebrated the presence or the absence of rigor in Derrida's work. Derrida himself uses the term a good deal throughout his career, usually in a positive (...) sense, although he also at least once, in passing, suggests the need to question the rigor of the concept of rigor itself. In this paper, I will outline the place of Kant in the Death Penalty Seminars and suggest that it is the very rigor attributed to Kant that makes him (rather than some other writers—whether supporters or opponents of the death penalty—whose arguments seem less rigorous to Derrida) an exemplary object for deconstructive attention, not for the first time in Derrida's work. Broadening the focus beyond the texts Derrida explicitly analyzes, I suggest that this kind of attention can also be fruitfully brought to bear on some more general arguments in Kant about right and justice. In conclusion, I suggest some implications of this situation for the still difficult issue of the more general relation between deconstruction and critique in the Kantian sense. (shrink)

Mathematical rigor is commonly formulated by mathematicians and philosophers using the notion of proof gap: a mathematical proof is rig­orous when there is no gaps in the mathematical reasoning of the proof. Any philosophical approach to mathematical rigor along this line requires then an account of what a proof gap is. However, the notion of proof gap makes sense only relatively to a given conception of valid mathematical reasoning, i.e., to a given conception of the validity of mathematical inference. A (...) proof gap can in particular be conceived as a failure in drawing a valid mathematical inference. The aim of this paper is to discuss two possible views of the validity of math­ematical inference with respect to their capacity to yield a plausible account of the intuitive notion(s) of proof gap present in mathematical practice. The first view is the one provided by the contemporary standards of mathematical rigor: a mathematical inference is valid if and only if its conclusion can be formally derived from its premises. We will argue that this conception does not lead to a plausible account of the intuitive notion(s) of proof gap. The second view is based on a new account of the validity of inference proposed by Prawitz: an inference is valid if and only if it consists in an operation that provides a ground for its conclusion given (previously obtained) grounds for its premises. We will first specify Prawitz's account to mathematical inference and we will then argue that the resulting ground-based account is able to capture various intuitive notions of proof gap as different types of failure in drawing valid mathematical inferences. We conclude that the ground-based account ap­pears of particular interest for the philosophy of mathematical practice, and we finally raise several challenges facing a full development of a ground-based account of the notions of mathematical rigor, proof gap and the validity of mathematical inference. (shrink)

American taxpayers spend $30 billion annually funding biomedical research. By some estimates, half of the results from these studies can't be replicated elsewhere-the science is simply wrong. Often, research institutes and academia emphasize publishing results over getting the right answers, incentivizing poor experimental design, improper methods, and sloppy statistics. Bad science doesn't just hold back medical progress, it can sign the equivalent of a death sentence. How are those with breast cancer helped when the cell on which 900 papers are (...) based turns out not to be a breast cancer cell at all? How effective could a new treatment for ALS be when it failed to cure even the mice it was initially tested on? In Rigor Mortis, award-winning science journalist Richard F. Harris reveals these urgent issues with vivid anecdotes, personal stories, and interviews with the nation's top biomedical researchers. We need to fix our dysfunctional biomedical system-now. (shrink)

In "Moses the Egyptian"--the centerpiece of Rigorism of Truth, the German philosopher Hans Blumenberg addresses two defining figures in the intellectual history of the twentieth century: Sigmund Freud and Hannah Arendt. Unpublished during his lifetime, this essay analyzes Freud's Moses and Monotheism and Arendt's Eichmann in Jerusalem, and discovers in both a principled rigidity that turns into recklessness because it is blind to the politics of the unknown. Offering striking insights into the importance of myth in politics and the (...) extent to which truth can be tolerated in adversity, the essay also provides one of the few instances where Blumenberg reveals his thinking about Judaism and Zionism. Rigorism of Truth also includes commentaries by Ahlrich Meyer that give a fuller understanding of the philosopher's engagement with Freud, Arendt, and the Eichmann trial, as well as situating these reflections in the broader context of Blumenberg's life and thought. (shrink)

Against the modern tendency to considerate just the formal-empirical knowledge as Science, and this one mathematized as much as possible, here many declarations of Aristotle are raised in order to show that the scientific rigour is not univocal but analogic: it is determined according to the nature of the object to be known. This is a so elementary epistemological rule that not knowing it is understood by that philosopher as apaideusia, i.e., lack of basic education in the knowledge sphere in (...) general. To the Stagirite, a pepaideuménos, i.e., a well educated spirit requires to every subject just the kind of rigour which is adequate to it, attempting not to impose whether the demonstrative or the mathematical rigour to the subject. It is specially truth for the theological Science, whose subject, by being transcendent, asks for a sui generis rigour which has to be so faithful as possible to it. (shrink)

This paper argues that a successful philosophical analysis of models and simulations must accommodate an account of mathematically rigorous results. Such rigorous results may be thought of as genuinely model-specific contributions, which can neither be deduced from fundamental theory nor inferred from empirical data. Rigorous results provide new indirect ways of assessing the success of models and simulations and are crucial to understanding the connections between different models. This is most obvious in cases where rigorous results map different models on (...) to one another. Not only does this put constraints on the extent to which performance in specific empirical contexts may be regarded as the main touchstone of success in scientific modelling, it also allows for the transfer of warrant across different models. Mathematically rigorous results can thus come to be seen as not only strengthening the cohesion between scientific strategies of modelling and simulation, but also as offering new ways of indirect confirmation. (shrink)

Euler famously used diagrams to illustrate syllogisms in his Lettres à une princesse d’Allemagne [1]. His diagrams are usually seen as suffering from a fatal “ambiguity problem” [11]: as soon as they involve intersecting circles, which are required for the representation of existential statements, it becomes unclear what exactly may be read off from them, and as Hammer & Shin conclusively showed, any set of reading conventions can lead to erroneous conclusions. I claim that Euler diagrams can, however, be used (...) rigorously, if they are read in conjunction with the premises they are supposed to illustrate. More precisely, I give rigorous “heterogeneous” inference rules (in the sense of Barwise and Etchemendy) – rules whose premises are a sentence and a diagram and whose conclusion is a sentence – which allow to use them safely. I conclude that one should abandon the preconception that diagrams can only be used rigorously if they can be given a context-independent semantics. Finally, I suggest that context-dependence is a widespread feature of diagrams: for instance, Mumma [12] noticed that what may be read off from a Euclidean diagram depends not only on the diagram’s appearance, but also on the way it was constructed. (shrink)

Part I of the present work outlined the rigorous application of information theory to a quantum mechanical system in a thermodynamic equilibrium state. The general formula developed there for the best-guess density operator $\hat \rho$ was indeterminate because it involved in an essential way an unspecified prior probability distribution over the continuumD H of strong equilibrium density operators. In Part II mathematical evaluation of $\hat \rho$ is completed after an epistemological analysis which leads first to the discretization ofD H and (...) then to the adoption of a suitable indifference axiom to delimit the set of admissible prior distributions. Finally, quantal formulas for information-theoretic and thermodynamic entropies are contrasted, and the entire work is summarized. (shrink)

Analyses in Greek geometry are traditionally seen as heuristic devices. However, many occurrences of analysis in formal treatises are difficult to justify in such terms. I show that Greek analysies of geometrics can also serve formal mathematical purposes, which are arguably incomplete without which their associated syntheses are arguably incomplete. Firstly, when the solution of a problem is preceded by an analysis, the analysis latter proves rigorously that there are no other solutions to the problem than those offered in the (...) synthesis. Secondly, whenever some construction assumption beyond ruler and compass is made, the problem is not only solvable by that assumption but is in fact equivalent to that assumption in a rigorous sense. (shrink)

A task of any moral theory is to account for both the rigidity and the flexibility of moral rules. Utilitarianism faces the problem of building rigidity into a framework that tends towards objectionable flexibility. Kantianism faces the problem of building flexibility into a framework that tends towards objectionable rigidity. I offer an argument on this front on behalf of Kantians. I show how Kantians can maintain that actions are right and wrong "in themselves," while still maintaining that such actions can (...) be corrupted under certain "nonideal" circumstances. (shrink)

The ArgumentIt has long been apparent that in the nineteenth century, mathematics in France and England developed along different lines. The differences, which might well be labelled stylistic, are most easy to see on the foundational level. At first this may seem surprising because it is such a fundamental area, but, upon reflection, it is to be expected. Ultimately discussions about the foundations of mathematics turn on views about what mathematics is, and this is a question which is answered by (...) a variety of different groups including mathematicians, students, curricular planners, parents, etc. Mathematical practice rests on some kind of mixture of the answers to this fundamental question which come from these diverse groups. Comparing the cultural matrices which supported mathematics in France and Britain in the first decades of the nineteenth century sheds light on the real though often subtle differences in the ways the subject was pursued in the two countries. (shrink)

A principle, according to which any scientific theory can be mathematized, is investigated. Social science, liberal arts, history, and philosophy are meant first of all. That kind of theory is presupposed to be a consistent text, which can be exhaustedly represented by a certain mathematical structure constructively. In thus used, the term “theory” includes all hypotheses as yet unconfirmed as already rejected. The investigation of the sketch of a possible proof of the principle demonstrates that it should be accepted rather (...) a metamathematical axiom about the relation of mathematics and reality. The main statement is formulated as follows: Any scientific theory admits isomorphism to some mathematical structure in a way constructive. Its investigation needs philosophical means. Husserl’s phenomenology is what is used, and then the conception of “bracketing reality” is modelled to generalize Peano arithmetic in its relation to set theory in the foundation of mathematics. The obtained model is equivalent to the generalization of Peano arithmetic by means of replacing the axiom of induction with that of transfinite induction. The sketch of the proof is organized in five steps: a generalization of epoché; involving transfinite induction in the transition between Peano arithmetic and set theory; discussing the finiteness of Peano arithmetic; applying transfinite induction to Peano arithmetic; discussing an arithmetical model of reality. Accepting or rejecting the principle, two kinds of mathematics appear differing from each other by its relation to reality. Accepting the principle, mathematics has to include reality within itself in a kind of Pythagoreanism. These two kinds are called in paper correspondingly Hilbert mathematics and Gödel mathematics. The sketch of the proof of the principle demonstrates that the generalization of Peano arithmetic as above can be interpreted as a model of Hilbert mathematics into Gödel mathematics therefore showing that the former is not less consistent than the latter, and the principle is an independent axiom. The present paper follows a pathway grounded on Husserl’s phenomenology and “bracketing reality” to achieve the generalized arithmetic necessary for the principle to be founded in alternative ontology, in which there is no reality external to mathematics: reality is included within mathematics. That latter mathematics is able to self-found itself and can be called Hilbert mathematics in honour of Hilbert’s program for self-founding mathematics on the base of arithmetic. The principle of universal mathematizability is consistent to Hilbert mathematics, but not to Gödel mathematics. Consequently, its validity or rejection would resolve the problem which mathematics refers to our being; and vice versa: the choice between them for different reasons would confirm or refuse the principle as to the being. An information interpretation of Hilbert mathematics is involved. It is a kind of ontology of information. The Schrödinger equation in quantum mechanics is involved to illustrate that ontology. Thus the problem which of the two mathematics is more relevant to our being is discussed again in a new way A few directions for future work can be: a rigorous formal proof of the principle as an independent axiom; the further development of information ontology consistent to both kinds of mathematics, but much more natural for Hilbert mathematics; the development of the information interpretation of quantum mechanics as a mathematical one for information ontology and thus Hilbert mathematics; the description of consciousness in terms of information ontology. (shrink)

This paper critically examines and evaluates Yacin Hamami’s reconstruction of the standard view of mathematical rigor. We will argue that the reconstruction offered by Hamami is premised on a strong and controversial epistemological thesis and a strong and controversial thesis in the philosophy of mind. Secondly, we will argue that Hamami’s reconstruction of the standard view robs it of its original philosophical rationale, i.e. making sense of the notion of rigor in mathematical practice.

Although the target article provides strong evidence against the locationist view, evidence for the constructionist view is inconclusive, because co-activation of brain regions does not necessarily imply connectivity between them. We propose a rigorous approach wherein connectivity between co-activated regions is first modeled using exploratory Granger causality, and then confirmed using dynamic causal modeling or Bayesian modeling.

The present paper examines the role of exact results in the theory of many‐body physics, and specifically the example of the Mermin‐Wagner theorem, a rigorous result concerning the absence of phase transitions in low‐dimensional systems. While the theorem has been shown to hold for a wide range of many‐body models, it is frequently ‘violated’ by results derived from the same models using numerical techniques. This raises the question of how scientists regulate their theoretical commitments in such cases, given that the (...) models, too, are often described as approximations to the underlying ‘full’ many‐body problem. (shrink)

The Rigor of a Certain Inhumanity is a rich and passionate, playful and perceptive work of philosophical analysis.

The classification of algebraic surfaces by the Italian School of algebraic geometry is universally recognized as a breakthrough in 20th-century mathematics. The methods by which it was achieved do not, however, meet the modern standard of rigor and therefore appear dubious from a contemporary viewpoint. In this article, we offer a glimpse into the mathematical practice of the three leading exponents of the Italian School of algebraic geometry: Castelnuovo, Enriques, and Severi. We then bring into focus their distinctive conception of (...) rigor and intuition. Unlike what is often assumed today, from their perspective, rigor is neither opposed to intuition nor understood as a unitary phenomenon – Enriques distinguishes between small-scale rigor and large-scale rigor and Severi between formal rigor and substantial rigor. Finally, we turn to the notion of mathematical objectivity. We draw from our case study in order to advance a multi-dimensional analysis of objectivity. Specifically, we suggest that various types of rigor may be associated with different conceptions of objectivity: namely, objectivity as faithfulness to facts and objectivity as intersubjectivity. (shrink)

Many arguments found in the physics literature involve concepts that are not well-defined by the usual standards of mathematics. I argue that physicists are entitled to employ such concepts without rigorously defining them so long as they restrict the sorts of mathematical arguments in which these concepts are involved. Restrictions of this sort allow the physicist to ignore calculations involving these concepts that might lead to contradictory results. I argue that such restrictions need not be ad hoc, but can sometimes (...) be justified by considering some of the metaphysical issues surrounding the question of the applicability of mathematics to physical reality. 1 Introduction 2 Rejecting inferential permissiveness 3 The agreement problem 4 Independent objections to the liberal view. (shrink)

Duhem's portrayal of the history of mathematics as manifesting calm and regular development is traced to his conception of mathematical rigor as an essentially static concept. This account is undermined by citing controversies over rigorous demonstration from the eighteenth and twentieth centuries.

The Clauser–Horne–Shimony–Holt (CHSH) inequality is a constraint that local hidden variable theories must obey. Quantum Mechanics predicts a violation of this inequality in certain experimental settings. Treatments of this subject frequently make simplifying assumptions about the probability spaces available to a local hidden variable theory, such as assuming the state of the system is a discrete or absolutely continuous random variable, or assuming that repeated experimental trials are independent and identically distributed. In this paper, we do two things: first, show (...) that the CHSH inequality holds even for completely general state variables in the measure-theoretic setting, and second, demonstrate how to drop the assumption of independence of subsequent trials while still being able to perform a hypothesis test that will distinguish Quantum Mechanics from local theories. The statistical strength of such a test is computed. (shrink)

Open peer commentary on the article “Design Research as a Variety of Second-Order Cybernetic Practice” by Ben Sweeting. Upshot: I reflect on the theme of honesty in research and discuss the adjoining requirements of rigor from an academic perspective. Central to my discussion is Glanville’s assertion that what researchers - from either science or design - presented was not what they actually thought and did.

Critics of evolutionary psychology object that it is not rigorous science compared to other evolutionary science. Advocates reply that it is rigorous science, and that the critics are uninformed. Still, informed people having opposing preconceptions of what counts as rigor may reach opposing evaluative conclusions. I shall clarify the very idea of rigorous evolutionary histories in relation to the basic objection that “evolution without history” is not rigorous.

A monumental and riveting account of how a poet, a physicist, and a philosopher pursued truth to the very limits of human apprehension and revealed the fundamental nature of our place in the universe Spiraling in the wreckage of a failed love affair, Argentine poet Jorge Luis Borges channeled his devastation into his work, reassessing the slippery nature of our own identities and the way we perceive reality, ultimately securing his place in the literary pantheon. Doggedly fighting against the scientific (...) establishment for his controversial interpretation of quantum mechanics, German physicist Werner Heisenberg dared to accept the experimental evidence at face value, leading him to a principle that has been a guiding light for physicists ever since. Prussian philosopher Immanuel Kant, horrified by the possibility that all knowledge might rest on uncertain grounds, undertook to test the limits of reason, placing human understanding on a firmer footing than ever before. What these three thinkers shared, in addition to their uncommon intellect, was their skepticism-not only of the accepted wisdom of their culture, but also of their own reasoning. What set them apart was their willingness to submit their ideas to the same rigor they would bring to someone else's. In so doing, they made extraordinary leaps in answering some of the most enduring questions about the nature of reality-about the flow of time in human consciousness, about the origins and nature of the universe, but most importantly, about the possibility of coming to know reality as it is itself. In an era like ours, in which dogma of all kinds seems to rule the day, the story of these thinkers serves as a crucial reminder that maverick thinking demands submitting our intuitions and even our own deeply held beliefs to the cold light of reason. In their lives and work we recognize that the mysteries of our place in the world may always loom over us, not as a threat, but as a reminder of our humble humanity. (shrink)

This paper examines whether Bruno Bauer's critical assessment of Jewish emancipation in Prussia is consistent with his other republican writings in the 1840s. It argues that Bauer's political position is a form of republican rigorism, according to which human emancipation requires identification with universal interests, and not the defence of particular identities. Rigorism involves the elimination of internal as well as external heteronomous influences, and implies shifting the boundaries between the juridical and the moral realms as defined by (...) Kant. Subjects' incentives for adopting the maxims that govern their external action are taken to be relevant to the assessment of the emancipatory potential of their deeds and claims. The paper distinguishes degrees of rigorism, and shows that Bauer's specific conclusions on the Jewish question, while not entirely unfounded by his political logic, are not strictly implied by his premises. Contrasting positions in his work are illustrated. (shrink)

"Mark Wilson aims to reconnect analytic philosophy with the evolving practicalities within science from which many of its grander concerns originally sprang. He offers an alternative history of how the subject might have developed had the insights of its philosopher/scientist forebears not been cast aside in the vain pursuit of 'ersatz rigor'"--.

Open texture is a kind of semantic indeterminacy first systematically studied by Waismann. In this paper, extant definitions of open texture will be compared and contrasted, with a view towards the consequences of open-textured concepts in mathematics. It has been suggested that these would threaten the traditional virtues of proof, primarily the certainty bestowed by proof-possession, and this suggestion will be critically investigated using recent work on informal proof. It will be argued that informal proofs have virtues that mitigate the (...) danger posed by open texture. Moreover, it will be argued that while rigor in the guise of formalisation and axiomatisation might banish open texture from mathematical theories through implicit definition, it can do so only at the cost of restricting the tamed concepts in certain ways. (shrink)

No livro I da Ethica Eudemia, Aristóteles dedica um capítulo a considerações acerca de seu método. No entanto, analisando passagens de outros tratados do autor, é possível concluir que há algo comum que perpassa as diversas considerações acerca de seu método, a saber: que o ponto de partida de toda investigação é dado pelo que é mais cognoscível a nós, e todo o procedimento de investigação visa chegar ao que é mais cognoscível em si mesmo – o conhecimento estrito do (...) objeto, que inclui compreender suas causas. O objetivo deste trabalho é tentar compreender como esse procedimento acontece na investigação moral, que opera no âmbito do discurso e, portanto, das definições. Para isso, pretendemos analisar como acontece a passagem da análise do que é dado na experiência em direção ao conhecimento de suas causas, que é próprio de outros tratados aristotélicos, para a análise das opiniões vagas e imprecisas em direção às definições estritas com as quais a Ethica Eudemia pretende operar. (shrink)

In previous publications we have criticized the usual application of information theory to quantal situations and proposed a new version of information-theoretic quantum statistics. This paper is the first in a two-part series in which our new approach is applied to the fundamental problem of thermodynamic equilibrium. Part I deals in particular with informational definitions of equilibrium and the identification of thermodynamic analogs in our modified quantum statistics formalism.

This paper has three goals: (i) to show that the foundational program begun in the Begriffsschroft, and carried forward in the Grundlagen, represented Frege's attempt to establish the autonomy of arithmetic from geometry and kinematics; the cogency and coherence of 'intuitive' reasoning were not in question. (ii) To place Frege's logicism in the context of the nineteenth century tradition in mathematical analysis, and, in particular, to show how the modern concept of a function made it possible for Frege to pursue (...) the goal of autonomy within the framework of the system of second-order logic of the Begriffsschrift. (iii) To address certain criticisms of Frege by Parsons and Boolos, and thereby to clarify what was and was not achieved by the development, in Part III of the Begriffsschrift, of a fragment of the theory of relations. (shrink)

In this second edition, Joseph Rychlak has retained his analysis of the philosophical antecedents of psychology and, at the same time, has considerably revised more complicated material illustration rigorous humanism to make the book more accessible for students. Rychlak here offers an analysis of the philosophical traditions underlying the social sciences and shows how functionalism came to dominate the modern science of psychology in America.

Leiter (2016) charges public philosophy with being “neoliberal”. To understand that charge better, I define, in §1, three versions of public philosophy which might be concerned and two pictures of its practice targeted by Leiter. I also compare two deliberative sites wherein those pictures may play out. In §2, I sketch how Leiter’s two paradoxes for “neoliberal” public philosophy lead to a revised public philosophy. §3 questions the paradoxes’ empirical grounding and scope. Lastly, in §4, I assume Leiter’s picture and (...) illustrate how philosophical dialogue, through appeal to personal self-image and “moral perceptions”, may still influence public discourse. I conclude that Leiter both over- and understates his case and that his conclusions require greater scrutiny. (shrink)