According to Aristotle, humans are the rational animal. The borderline between rationality and irrationality is fundamental to many aspects of human life including the law, mental health, and language interpretation. But what is it to be rational? One answer, deeply embedded in the Western intellectual tradition since ancient Greece, is that rationality concerns reasoning according to the rules of logic – the formal theory that specifies the inferential connections that hold with certainty between propositions. Piaget viewed logical reasoning as defining (...) the end-point of cognitive development; and contemporary psychology of reasoning has focussed on comparing human reasoning against logical standards. (shrink)

We provide an overview of three ways in which the expression “Historical epistemology” (HE) is often understood: (1) HE as a study of the history of higher-order epistemic concepts such as objectivity, observation, experimentation, or probability; (2) HE as a study of the historical trajectories of the objects of research, such as the electron, DNA, or phlogiston; (3) HE as the long-term study of scientific developments. After laying out various ways in which these agendas touch on current debates within both (...) epistemology and philosophy of science (e.g., skepticism, realism, rationality of scientific change), we conclude by highlighting three topics as especially worthy of further philosophical investigation. The first concerns the methods, aims and systematic ambitions of the history of epistemology. The second concerns the ways in versions of HE can be connected to versions of naturalized and social epistemologies. The third concerns the philosophy of history, and in particular the level of analysis at which a historical analysis should aim. (shrink)

In this paper, I present a brief (and more than a little potted) history of the concepts of reason, rationality, reasonableness, and reasons in modern European philosophy and consider whether this history might support the "Anscombean" conclusion that, "The concepts of rationality and reasons ought to jettisoned if this is psychologically possible; because they are survivals, or derivatives from survivals, from an earlier conception of psychology and philosophy which no longer generally survives, and are only harmful without it.".

In her Pharmaceutical Freedom, Jessica Flanigan argues that antibiotics can be regulated consistent with her otherwise largely deregulatory view with respect to pharmaceuticals and recreational drugs. I contend in this essay that the reasons for justifying antibiotic regulation are reasons that can be offered to justify the regulation of many other drugs, both pharmaceutical and recreational. After laying out the specifics of Flanigan’s view, I suggest that it is amenable to the regulation of drugs like varenicline. Though such drugs can (...) legitimately improve the quality of a patient’s life by helping them quit smoking, they could be permissibly regulated if they expose others to impermissible risks. I then argue that recreational drugs like alcohol could be regulated using the same reasoning. In the penultimate section of this essay, I anticipate objections that one might have to my extension of arguments favoring antibiotic regulation to drugs correlated with aggression. Flanigan might find my extrapolation of her view as entirely plausible and accept that her view is relatively friendly to these regulations, or she might reconsider her antibiotic caveat if these regulations are overly paternalistic on her understanding. I conclude by briefly considering the benefits and drawbacks of adopting each view. (shrink)

In this paper, I clarify and defend a provocative hypothesis offered by Bernard Williams, namely, that modern people are much more likely to speak in terms of master-concepts like “good” or “right,” and correspondingly less likely to think and speak in the pluralistic terms favored by certain Ancient societies. By conducting a close reading of the Platonic dialogues Charmides and Laches, I show that the figure of Socrates plays a key historical role in this conceptual shift. Once we understand that (...) our narrow, reductionist focus on “thin” ethical concepts is a contingent historical development, we are, I claim, in a much better position to evaluate it. (shrink)

This is a review of the issue of randomness in quantum mechanics, with special emphasis on its ambiguity; for example, randomness has different antipodal relationships to determinism, computability, and compressibility. Following a philosophical discussion of randomness in general, I argue that deterministic interpretations of quantum mechanics are strictly speaking incompatible with the Born rule. I also stress the role of outliers, i.e. measurement outcomes that are not 1-random. Although these occur with low probability, their very existence implies that the no-signaling (...) principle used in proofs of randomness of outcomes of quantum-mechanical measurements should be reinterpreted statistically, like the second law of thermodynamics. In three appendices I discuss the Born rule and its status in both single and repeated experiments, review the notion of 1-randomness that in various guises was investigated by Kolmogorov and others and treat Bell’s Theorem and the Free Will Theorem with their implications for randomness. (shrink)

From its first significant appearance in physics, the notion of probability has been linked in the minds of physicists with the notion of uncertainty. But the link may prove to be tenuous, if quantum mechanics, construed in terms of the Everett interpretation, is anything to go by.

Schurz (2019, ch. 4) argues that probabilistic accounts of induction fail. In particular, he criticises probabilistic accounts of induction that appeal to direct inference principles, including subjective Bayesian approaches (e.g., Howson 2000) and objective Bayesian approaches (see, e.g., Williamson 2017). In this paper, I argue that Schurz’ preferred direct inference principle, namely Reichenbach’s Principle of the Narrowest Reference Class, faces formidable problems in a standard probabilistic setting. Furthermore, the main alternative direct inference principle, Lewis’ Principal Principle, is also hard to (...) reconcile with standard probabilism. So, I argue, standard probabilistic approaches cannot appeal to direct inference to explicate the logic of induction. However, I go on to defend a non-standard objective Bayesian account of induction: I argue that this approach can both accommodate direct inference and provide a viable account of the logic of induction. I then defend this account against Schurz’ criticisms. (shrink)

Prior to 1651, Hobbes was agnostic about the existence of God. Hobbes argued that God’s existence could neither be demonstrated nor proved, so that those who reason about God’s existence will systematically vacillate, sometimes thinking God exists, sometimes not, which for Hobbes is to say they will doubt God’s existence. Because this vacillation or doubt is inherent to the subject, reasoners like himself will judge that settling on one belief rather than another is epistemically unjustified. Hobbes’s agnosticism becomes apparent once (...) we attend to his distinctions between the propositional attitudes one might adopt towards theological claims, including supposing, thinking, having faith and knowing. (shrink)

The work of Hugh MacColl (1837–1909) suffered the same fate after his death as before it:despite being vaguely alluded to and in part even commended, on the whole it has remained an unknown quantity. Even worse, those of his ideas which have played a decisive role in the history of logic have been credited to his successors; this is especially the case with the definition of strict implication and the first formal development of formal modal logic. This paper takes an (...) initial step towards a rectification of this unfortunate misrepresentation, presenting a bibliography of MacColl’s most significant publications with particular regard to their reception. (shrink)

The paper discusses the place and the status of fallacies in Arnauld and Nicole’s Port-Royal Logic, which seems to be the first book to introduce a radical change from the traditional Aristotelian account of fallacies. The most striking innovation is not in the definition of a fallacy but in the publication of a new list of fallacies, dropping some Aristotelian ones and adding more than ten new ones. The first part of the paper deals with the context of the book’s (...) publication. We then show the influence of Cartesian and Augustinian/Pascalian philosophy on the whole book, especially their common critical views about logic, dialectic and their traditional academic teaching. The third part of the paper discusses the two chapters on fallacies. It focuses on their place in the book and their relation with its general orientation, before turning to their content, closely connected with some major concerns of the time. (shrink)

Probability as understood today, namely as a quantitative notion expressible by means of a function ranging in the interval between 0–1, took shape in the mid-17th century, and presents both a mathematical and a philosophical aspect. Of these two sides, the second is by far the most controversial, and fuels a heated debate, still ongoing. After a short historical sketch of the birth and developments of probability, its major interpretations are outlined, by referring to the work of their most prominent (...) representatives. The final section addresses the question of whether any of such interpretations can presently be considered predominant, which is answered in the negative. (shrink)

How should probabilities be interpreted in causal models in the social and health sciences? In this paper we take a step towards answering this question by investigating the case of cancer in epidemiology and arguing that the objective Bayesian interpretation is most appropriate in this domain.

My aim in this paper is to take a closer look at an influential argument that purports to prove that the existence of cultural prohibitions could never be explained by biological inhibitions. The argument is two-pronged. The first prong reduces to the claim: inhibitions cannot cause prohibitions simply because inhibitions undermine the raison dêtre of prohibitions. The second strategy consists in arguing that inhibitions cannot cause prohibitions because the two differ importantly in their contents. I try to show that both (...) claims fail. (shrink)

Topics in Cognitive Science, Volume 14, Issue 3, Page 451-466, July 2022.

In IV, xvii, 19–22 of his Essay, Locke employs Latin labels for four kinds of argument, of which one (ad hominem) was already in circulation and one (ad judicium) has never had much currency. The present proposal seeks to locate and clarify what Locke was aiming to describe, and to contrast what he says with some subsequent uses that have been made of these labels as if they named fallacies. Though three of the four kinds of argument that Locke picks (...) out are often less than decisive, he casts no aspersion on the legitimacy of their use in debate. (shrink)

The purpose of this paper is to discuss the role of financial practice in the development of mathematics as applied in human judgement. The basis of the paper is in historical research from the 1990s that argues that the monetisation of western commerce, which abstracted value into quantified price, was synthesised with scholastic analysis resulting in a “mathematical mechanistic world picture” that led to the widespread use of mathematics in science from the seventeenth century. An aspect of this process was (...) the quantification of chance that led to the development of mathematical probability, the branch of mathematics most relevant to judgement and the focus of this paper. Ideas from this historical research are related to the fundamental theorem of asset pricing, the foundational theory of contemporary financial mathematics. The paper observes that vestiges of medieval scholastic attitudes to financial ethics can be discerned in the FTAP, offering a novel interpretation of the mathematical theorem. The paper then considers the Dutch book argument, the most popular justification for subjective probability. The paper’s main contribution is in describing the significance of financial practice in validating the DBA and the paper explains how the FTAP addresses some criticisms of how the DBA represents beliefs. The conclusions emphasise the distinction between pure and practical reasoning and that this should be mirrored in a distinction between the mathematics of physica and practica. This point is important as mathematics is becoming more widespread in modelling, and directing, social systems. (shrink)

Choices rarely deal with certainties; and, where assertoric logic and modal logic are insufficient, those seeking to be reasonable turn to one or more things called “probability.” These things typically have a shared mathematical form, which is an arithmetic construct. The construct is often felt to be unsatisfactory for various reasons. A more general construct is that of a preordering, which may even be incomplete, allowing for cases in which there is no known probability relation between two propositions or between (...) two events. Previous discussion of incomplete preorderings has been as if incidental, with researchers focusing upon preorderings for which quantifications are possible. This article presents formal axioms for the more general case. Challenges peculiar to some specific interpretations of the nature of probability are brought to light in the context of these propositions. A qualitative interpretation is offered for probability differences that are often taken to be quantified. A generalization of Bayesian updating is defended without dependence upon coherence. Qualitative hypothesis testing is offered as a possible alternative in cases for which quantitative hypothesis testing is shown to be unsuitable. [NB: There is a transcription error in (A6), the quantification “∀(Y,c₂)” should be applied within the large parentheses to the proposition on the third row. You have my apologies!]. (shrink)

Contre la thèse qui réduit le raisonnement juridique à une simple rhétorique, l’article entend montrer que ce raisonnement répond à une exigence de vérité. Une telle démonstration exige de repenser la relation entre logique et rhétorique dans le champ juridique. La logique ici mobilisée est une logique de la probabilité, appropriée à la rationalité pragmatique. C’est du même coup la relation entre logique juridique et logique probabiliste qui se trouve interrogée, d’une part dans une perspective historique, d’autre part en tenant (...) compte des études contemporaines sur le sujet. (shrink)