We provide a new interpretation of Zeno’s Paradox of Measure that begins by giving a substantive account, drawn from Aristotle’s text, of the fact that points lack magnitude. The main elements of this account are (1) the Axiom of Archimedes which states that there are no infinitesimal magnitudes, and (2) the principle that all assignments of magnitude, or lack thereof, must be grounded in the magnitude of line segments, the primary objects to which the notion of linear magnitude applies. Armed (...) with this account, we are ineluctably driven to introduce a highly constructive notion of (outer) measure based exclusively on the total magnitude of potentially infinite collections of line segments. The Paradox of Measure then consists in the proof that every finite or potentially infinite collection of points lacks magnitude with respect to this notion of measure. We observe that the Paradox of Measure, thus understood, troubled analysts into the 1880’s, despite their knowledge that the linear continuum is uncountable. The Paradox was ultimately resolved by Borel in his thesis of 1893, as a corollary to his celebrated result that every countable open cover of a closed line segment has a finite sub-cover, a result he later called the “First Fundamental Theorem of Measure Theory.” This achievement of Borel has not been sufficiently appreciated. We conclude with a metamathematical analysis of the resolution of the paradox made possible by recent results in reverse mathematics. (shrink)

With the systematic aim of clarifying the phenomenon sometimes described as “the intellectual apprehension of first principles,” Descartes’ first principle par excellence is interpreted before the historical backcloth of Aristotle’s Posterior Analytics. To begin with, three “faces” of the cogito are distinguished: (1) the proto-cogito (“I think”), (2) the cogito proper (“I think, therefore I am”), and (3) the cogito principle (“Whatever thinks, is”). There follows a detailed (though inevitably somewhat conjectural) reconstruction of the transition of the mind from (1) (...) via (3) to (2) and back again to (3). What emerges is, surprisingly, a non-circular, non-logical, and ultimately non-mysterious process by which first principles implicitly contained in a complex intuition are gradually rendered explicit (and, if abstract, grasped in their abstract universality). This process bears a striking family resemblance to that intuitive induction (“grasping the universal in the particular”) which Aristotle scholars have distinguished from empirical forms of induction. (shrink)

There is little agreement about Aristotle’s philosophy of geometry, partly due to the textual evidence and partly part to disagreement over what constitutes a plausible view. I keep separate the questions ‘What is Aristotle’s philosophy of geometry?’ and ‘Is Aristotle right?’, and consider the textual evidence in the context of Greek geometrical practice, and show that, for Aristotle, plane geometry is about properties of certain sensible objects—specifically, dimensional continuity—and certain properties possessed by actual and potential compass-and-straightedge drawings qua quantitative and (...) continuous. For their part, the objects of stereometry are potential sensible three-dimensional figures qua quantitative and continuous. (shrink)

The purpose of this work is to address the relation existing between ancient Greek practical geometry and ancient Greek pure geometry. In the first part of the work, we will consider practical and pure geometry and how pure geometry can be seen, in some respects, as arising from an idealization of practical geometry. From an analysis of relevant extant texts, we will make explicit the idealizations at play in pure geometry in relation to practical geometry, some of which are basically (...) explicit in definitions, like that of segments in Euclid’s Elements. Then, we will address how in pure geometry we, so to speak, “refer back” to practical geometry. This occurs in two ways. One, in the propositions of pure geometry. The other, when applying pure geometry. In this case, geometrical objects can represent practical figures like, e.g., a practical segment. (shrink)

This inaugural handbook documents the distinctive research field that utilizes history and philosophy in investigation of theoretical, curricular and pedagogical issues in the teaching of science and mathematics. It is contributed to by 130 researchers from 30 countries; it provides a logically structured, fully referenced guide to the ways in which science and mathematics education is, informed by the history and philosophy of these disciplines, as well as by the philosophy of education more generally. The first handbook to cover the (...) field, it lays down a much-needed marker of progress to date and provides a platform for informed and coherent future analysis and research of the subject. -/- The publication comes at a time of heightened worldwide concern over the standard of science and mathematics education, attended by fierce debate over how best to reform curricula and enliven student engagement in the subjects There is a growing recognition among educators and policy makers that the learning of science must dovetail with learning about science; this handbook is uniquely positioned as a locus for the discussion. -/- The handbook features sections on pedagogical, theoretical, national, and biographical research, setting the literature of each tradition in its historical context. Each chapter engages in an assessment of the strengths and weakness of the research addressed, and suggests potentially fruitful avenues of future research. A key element of the handbook’s broader analytical framework is its identification and examination of unnoticed philosophical assumptions in science and mathematics research. It reminds readers at a crucial juncture that there has been a long and rich tradition of historical and philosophical engagements with science and mathematics teaching, and that lessons can be learnt from these engagements for the resolution of current theoretical, curricular and pedagogical questions that face teachers and administrators. (shrink)

Mathematicians often speak of conjectures, yet unproved, as probable or well-confirmed by evidence. The Riemann Hypothesis, for example, is widely believed to be almost certainly true. There seems no initial reason to distinguish such probability from the same notion in empirical science. Yet it is hard to see how there could be probabilistic relations between the necessary truths of pure mathematics. The existence of such logical relations, short of certainty, is defended using the theory of logical probability (or objective Bayesianism (...) or non-deductive logic), and some detailed examples of its use in mathematics surveyed. Examples of inductive reasoning in experimental mathematics are given and it is argued that the problem of induction is best appreciated in the mathematical case. (shrink)

This paper aims to establish the importance of mathematical thinking in the work of Vilém Flusser. For this purpose highlights the concept of escalation of abstraction with which the Czech German philosopher finishes by reversing the top of the traditional pyramid of knowledge, we know from Plato and Aristotle. It also assumes the implicit cultural revolution in the refinement of the numerical element in a process of gradual abandonment of purely alphabetic code, highlights the new key code, together with the (...) technological and telematic culture and uses the concepts of game theory, of probability theory and computing to analize the society and culture. Of particular importance is the affirmation of a new kind of imagination, a projective one, ranging from the model to the world. Today's society and culture can´t be understood without resorting to the concepts and results coined and made ​​in the course of developing a type of thinking entirely dominated by the mathematics. The limits and boundaries of scientific disciplines overlap under number development, requiring reflection and rethinking traditional concepts of social and natural sciences. (shrink)

In the eighth chapter of De Sophisticis Elenchis, Aristotle introduces a mode of sophistical refutation that constitutes an addition to the taxonomy of the earlier chapters of the treatise. The new mode is pseudo-scientific refutation, or “the [syllogism or refutation] which though real, [merely] appears appropriate to the subject matter”. Against the grain of its most commonly accepted reading, I argue that Aristotle is not concerned in SE 8 to establish that both the apparent refutations of SE 4–7 and pseudo-scientific (...) refutations issue in false conclusions. His concern rather is to provide a causal analysis of both classes of apparent refutation alike which will explain why both kinds of apparent refutation are sophistical – and whose solutions are therefore the task of no special science but of a dialectical σλλογιστιϰή τέχνη. I conclude my analysis with the observation that Aristotle exploits the results of SE 8 to fend off inSE 9, 10, and 11 respectively a triad of threats to the very existence of a τέχνη of the resolution of sophistical refutation. The three threats are: the impossibility of omniscience; the relativity of semantic beliefs; and the incapacity of a questioner ignorant of a science to expose the ignorance of a pretender to scientific expertise. (shrink)

The starting point of the following considerations is a case study concerning the discovery of Halley's comet and the theoretical description of its path. It is shown that the set of objects involved in that system and the time interval during which their paths are observed are determined in a theory dependent way – thereby making use of the very theory later used for that system's theoretical description. Metatheoretical consequences this fact has with respect to the structuralist view of empirical (...) theories are discussed in detail. German Den Ausgangspunkt der folgenden Überlegungen bildet eine Fallstudie, die der Entdeckung und theoretischen Beschreibung des Halleyschen Kometen gewidmet ist. Es wird gezeigt, dass bei diesem System die Menge der involvierten Objekte und die Zeitintervalle, über die sich die Beobachtung der Bahnen dieser Objekte erstreckt, in theorieabhängiger Weise bestimmt werden – und zwar in Abhängigkeit von genau derjenigen Theorie, die anschließend zur theoretischen Beschreibung des Systems eingesetzt wird. Metatheoretische Konsequenzen, die sich aus diesem Umstand insbesondere für das strukturalistische Theorienkonzept ergeben, werden im Detail analysiert. (shrink)

La filosofía de las matemáticas de Aristóteles es una investigación acerca de tres asuntos diferentes pero complementarios: el lugar epistemológico de las matemáticas en el organigrama de las ciencias teoréticas o especulativas; el estudio del método usado por el matemático para elaborar sus doctrinas, sobre todo la geometría y la aritmética; y la averiguación del estatuto ontológico de las entidades matemáticas. Para comprender lo peculiar de la doctrina aristotélica es necesario tener en cuenta que su principal interés está en poner (...) en relación la matemática con la filosofía primera u ontología y la física, y salvaguardar el campo de conocimiento propio de cada una de ellas. (shrink)

This article proposes an interpretation of the chapters of theNicomachean Ethicsconcerning exchange and friendship. Rejecting approaches where Aristotle anticipates modern labour or need-based theories of value, the article claims that those notions of labour and need are required for a satisfactory interpretation of the most obscure passages of Book V. Finally, Aristotle's texts on exchange and friendship are related in such a way that the latter, since it is free from any political considerations, allows us to better understand the philosopher's (...) view on exchange. (shrink)

In a recent paper Johan van Benthem reviews earlier work done by himself and colleagues on ‘natural logic’. His paper makes a number of challenging comments on the relationships between traditional logic, modern logic and natural logic. I respond to his challenge, by drawing what I think are the most significant lines dividing traditional logic from modern. The leading difference is in the way logic is expected to be used for checking arguments. For traditionals the checking is local, i.e. separately (...) for each inference step. Between inference steps, several kinds of paraphrasing are allowed. Today we formalise globally: we choose a symbolisation that works for the entire argument, and thus we eliminate intuitive steps and changes of viewpoint during the argument. Frege and Peano recast the logical rules so as to make this possible. I comment also on the traditional assumption that logical processing takes place at the top syntactic level, and I question Johan’s view that natural logic is ‘natural’. (shrink)

…all men begin… by wondering that things are as they are…as they do about…the incommensurability of the diagonal of the square with the side; for it seems wonderful to all who have not yet seen the reason, that there is a thing which cannot be measured even by the smallest unit. But we must end in the contrary and, according to the proverb, the better state, as is the case in these instances too when men learn the cause; for there (...) is nothing which would surprise a geometer so much as if the diagonal turned out to be commensurable. (shrink)

This article focusses on the generality of the entities involved in a geometric proof of the kind found in ancient Greek treatises: it shows that the standard modern translation of Greek mathematical propositions falsifies crucial syntactical elements, and employs an incorrect conception of the denotative letters in a Greek geometric proof; epigraphic evidence is adduced to show that these denotative letters are ‘letter-labels’. On this basis, the article explores the consequences of seeing that a Greek mathematical proposition is fully general, (...) and the ontological commitments underlying the stylistic practice. (shrink)

Equally surprisingly, Descartes’s paranoid belief was shared by several contemporary mathematicians, among them Isaac Barrow, John Wallis and Edmund Halley. (Huxley 1959, pp. 354-355.) In the light of our fuller knowledge of history it is easy to smile at Descartes. It has even been argued by Netz that analysis was in fact for ancient Greek geometers a method of presenting their results (see Netz 2000). But in a deeper sense Descartes perceived something interesting in the historical record. We are looking (...) in vain in the writings of Greek mathematicians for a full explanation of what this famous method was. And I will argue for an answer to the question why this lacuna is there: Not because Greek geometers wanted to hide this method, but because they did not fully understand it. It is instructive to note the ambivalent attitude of the most rigorous mathematician of the period, Isaac Newton, to the method of analysis. He used it himself in his own mathematical work and in the expositions of that work. Yet when the mathematical push came to physical and cosmological shove, he formulated his Principia entirely in.. (shrink)

This paper aims to show that an examination of some passages in Aristotle’s work can contribute to the resolution of crucial problems related to the interpretation of ancient geometrical analysis. In this context, we will focus in particular on the famous passage of the Posterior Analytics in which Aristotle cryptically refers to the analysis practised by the geometers and we will show the fundamental importance of this passage for a correct understanding of ancient geometrical analysis.

In Metaph. Β and Γ, Aristotle claims that universal principles, such as the principle of non contradiction or the principle of excluded middle, are principles of demons­trations. Besides the technical question of the way in which such principles are principles of demonstrations, this paper raises the question why Aristotle insists on their relation to demons­trations in the Metaphysics and not in Analytics. The answer proposed is that demons­trations use these universal principles because they are to reveal the stucture of reality, (...) and that these principles are principles of reality.But in calling these principles « syllogistical » principles too, Aristotle seems to assign to them a quite different role which has not been theorized. On one hand, this determination is inconsistent with the two other ones (laws of being, principles of demonstrations) since a law of reasoning as such belongs to formal logic and not to ontology. But on the other hand, Aristotle gives himself (Prior Analytics, I, 15) examples of valid syllogisms which admit of contradiction in the premisses, which means that he was perfectly aware of this difficulty, even though he left indeterminate the logical role of these universal principles. (shrink)

ArgumentThis paper argues for the viability of a different philosophical point of view concerning classical Greek geometry. It reviews Reviel Netz's interpretation of classical Greek geometry and offers a Deleuzian, post-structural alternative. Deleuze's notion of haptic vision is imported from its art history context to propose an analysis of Greek geometric practices that serves as counterpoint to their linear modular cognitive narration by Netz. Our interpretation highlights the relation between embodied practices, noisy material constraints, and operational codes. Furthermore, it sheds (...) some new light on the distinctness and clarity of Greek mathematical conceptual divisions. (shrink)

This historiographical study aims at introducing the category of “situated mathematics” to the case of Ancient Egypt. However, unlike Situated Learning Theory, which is based on ethnographic relativity, in this paper, the goal is to analyze a mathematical craft knowledge based on concrete particulars and case studies, which is ubiquitous in all human activity, and which even covers, as a specific case, the Hellenistic style, where theoretical constructs do not stand apart from practice, but instead remain grounded in it.The historiographic (...) interpretation that we will give of situated mathematics is inscribed in a characterization of mathematical styles that focuses on the role of mathematical practice. This categorization describes three types of mathematization, where, on the one hand, type I represents the classical and dominant Hellenocentric approach, which seeks to generate a body of principles that could then be applied in other fields. On the other hand, types II and III represent two kinds of situated mathematics, a parametrized and a concrete one. Type II proceeds in the opposite direction from Type I describing an application of a previously obtained theory. That is, given a practice in any domain, it seeks to build a mathematical systematization a posteriori to explain said practice. Finally, type III starts from a concrete practice and develops another similar practice that explains analogically the relationship.Based on the typology adopted, we seek to describe a case study within ancient Egyptian mathematics, which reveals how it is possible to subsume it in the two types of situated mathematization II and III. The foregoing will allow to bridge the gap between theory and practice. (shrink)

Pour rendre compte de la première démonstration d’existence d’une grandeur irrationnelle, les historiens des sciences et les commentateurs d’Aristote se réfèrent aux textes sur l’incommensurabilité de la diagonale qui se trouvent dans les Premiers Analytiques, les plus anciens sur la question. Les preuves usuelles proposées dérivent d’un même modèle qui se trouve à la fin du livre X des Éléments d’Euclide. Le problème est que ses conclusions, passant par la représentation des fractions comme rapport de deux entiers premiers entre eux, (...) i.e. la proposition VII.22 des Éléments, ne correspondent pas aux écrits aristotéli­ciens. Dans cet article, nous proposons une nouvelle démonstration, conforme aux textes des Analytiques, fondés sur des résultats très anciens de la théorie du pair et de l’impair. Ne passant pas par la proposition VII.22, ni par aucune autre propriété établie par l’absurde, cette irrationalité apparaît comme le premier résultat que l’on ne pouvait établir par une autre méthode. L’importance de ce résultat, révélant un nouveau domaine mathématique, celui des grandeurs irrationnelles, rend compte de la centralité que cette forme de raisonnement acquiert alors, d’abord en mathématique, puis dans tout type de discours rationnel. À partir des conséquences qui suivent de cette nouvelle démonstration, on peut interpréter très simplement la leçon sur les irrationnels du passage mathématique figurant dans le Théétète de Platon (147d-148b), ce que nous ferons dans un article à paraître dans un prochain numéro. (shrink)

Biton’s Construction of Machines of War and Catapults describes six machines by five engineers or inventors; the fourth machine is a rolling elevatable scaling ladder, named sambukē, designed by one Damis of Kolophōn. The first sambukē was invented by Herakleides of Taras, in 214 BCE, for the Roman siege of Syracuse. Biton is often dismissed as incomprehensible or preposterous. I here argue that the account of Damis’ device is largely coherent and shows that Biton understood that Damis had built a (...) machine that embodied Archimedean principles. The machine embodies three such principles: (1) the proportionate balancing of the torques on a lever (from Plane Equilibria, an early work); (2) the concept of specific gravity or density (from Floating Bodies, a late work); and (3) the κοχλίας, i.e., a worm drive (invented ca 240 BCE), with the toothed wheel functioning as the horizontal axis of rotation of the elevated ladder. Moreover, the stone-thrower of Isidoros of Abydos (the second machine in Biton) also embodies the κοχλίας. (shrink)

Reagere, reactio does not belong to classical Latin. Reagere appears, as late as the fourth century A.D., in Avienus, but not reactio. Nonetheless, antiquity was not unaware of the concept of reciprocal action, where the “patient” reacts in return on the agent. The Aristotelian doctrine of antiperistasis occupied physicists up until the time of Galileo: “All movers, as long as they move, are at the same time moved.” The Latin authors dispense with reagere and reactio. It is the verb pati, (...) designating the passive state to which the prefix re is added in the aphorism attributed to the Scholastics in the 18th century dictionaries: omnis agens agendo repatitur. (shrink)

I present a systematic interpretation of the foundational purpose of constructions in ancient Greek geometry. I argue that Greek geometers were committed to an operationalist foundational program, according to which all of mathematics—including its entire ontology and epistemology—is based entirely on concrete physical constructions. On this reading, key foundational aspects of Greek geometry are analogous to core tenets of 20th-century operationalist/positivist/constructivist/intuitionist philosophy of science and mathematics. Operationalism provides coherent answers to a range of traditional philosophical problems regarding classical mathematics, such (...) as the epistemic warrant and generality of diagrammatic reasoning, superposition, and the relation between constructivism and proof by contradiction. Alleged logical flaws in Euclid can be interpreted as sound operationalist reasoning. Operationalism also provides a compelling philosophical motivation for the otherwise inexplicable Greek obsession with cube duplication, angle trisection, and circle quadrature. Operationalism makes coherent sense of numerous specific choices made in this tradition, and suggests new interpretations of several solutions to these problems. In particular, I argue that: Archytas’s cube duplication was originally a single-motion machine; Diocles’s cissoid was originally traced by a linkage device; Greek conic section theory was thoroughly constructive, based on the conic compass; in a few cases, string-based constructions of conic sections were used instead; pointwise constructions of curves were rejected in foundational contexts by Greek mathematicians, with good reason. Operationalism enables us to view the classical geometrical tradition as a more unified and philosophically aware enterprise than has hitherto been recognised. (shrink)