This paper sets out to evaluate the claim that Aristotle’s Assertoric Syllogistic is a relevance logic or shows significant similarities with it. I prepare the grounds for a meaningful comparison by extracting the notion of relevance employed in the most influential work on modern relevance logic, Anderson and Belnap’s Entailment. This notion is characterized by two conditions imposed on the concept of validity: first, that some meaning content is shared between the premises and the conclusion, and second, that the premises (...) of a proof are actually used to derive the conclusion. Turning to Aristotle’s Prior Analytics, I argue that there is evidence that Aristotle’s Assertoric Syllogistic satisfies both conditions. Moreover, Aristotle at one point explicitly addresses the potential harmfulness of syllogisms with unused premises. Here, I argue that Aristotle’s analysis allows for a rejection of such syllogisms on formal grounds established in the foregoing parts of the Prior Analytics. In a final section I consider the view that Aristotle distinguished between validity on the one hand and syllogistic validity on the other. Following this line of reasoning, Aristotle’s logic might not be a relevance logic, since relevance is part of syllogistic validity and not, as modern relevance logic demands, of general validity. I argue that the reasons to reject this view are more compelling than the reasons to accept it and that we can, cautiously, uphold the result that Aristotle’s logic is a relevance logic. (shrink)

The ways in which the Aristotelian sciences are related to each other has been discussed in the literature, with some focus on the subalternate sciences. While it is acknowledged that Aristotle, and Plato as well, was concerned as well with how the arts were related to one another, less attention has been paid to Aristotle's views on relationships among the arts. In this paper, I argue that Aristotle's account of the subalternate sciences helps shed light on how Aristotle saw the (...) art of rhetoric relating to dialectic and politics. Initial motivation for comparing rhetoric with the subalternate sciences is Aristotle's use of the language of boundary transgression, germane to the Posterior Analytics, when discussing rhetoric’s boundaries, as well as the language of "over" and "under" found in APo. First, I discuss three passages in Rhetoric Book I and argue that Garver's (1988) account cannot be correct. Second, I look to the subalternate sciences, especially focusing on optics and the distinction between "unqualified" optics and mathematical optics. Third, I discuss rhetoric's dependence on both dialectic and politics. (shrink)

The concept of “necessity of thought” plays a central role in Dag Prawitz’s essay “Logical Consequence from a Constructivist Point of View” (Prawitz 2005). The theme is later developed in various articles devoted to the notion of valid inference (Prawitz, 2009, forthcoming a, forthcoming b). In section 1 I explain how the notion of necessity of thought emerges from Prawitz’s analysis of logical consequence. I try to expound Prawitz’s views concerning the necessity of thought in sections 2, 3 and 4. (...) In sections 5 and 6 I discuss some problems arising with regard to Prawitz’s views. (shrink)

This chapter discusses the first part of Aristotle's Posterior Analytics A-33, 88b30-89a10. I claim that Aristotle is not concerned with an epistemological distinction between knowledge and belief in general. He is rather making a contrast between scientific knowledge (which is equivalent to explanation by the primarily appropriate cause) and some explanatory beliefs that falls short of capturing the primarily appropriate cause.

In his 1910 book On the principle of contradiction in Aristotle, Jan Łukasiewicz claims that syllogistic is independent of the principle of contradiction . He also argues that Aristotle would have defended such a thesis in the Posterior Analytics. In this paper, we first show that Łukasiewicz's arguments for these two claims have to be rejected. Then, we show that the thesis of the independence of assertoric syllogistic vis-à-vis PC is nevertheless true. For that purpose, we first establish that there (...) is no possibility to account for Aristotle's original views on syllogistic without using per impossibile deductions. At last, following an idea due to Smith 1983, we prove that there is a complete reconstruction of assertoric syllogistic using ecthesis instead of reductio ad absurdum. Contrary to what is claimed in Smith 1983, we show that Smith's system SE has to be improved for such a reconstruction. This results in an ecthetic system which is complete with respect to syllogistic arguments, not explosi.. (shrink)

This paper discusses the contrast between scientific knowledge and opinion as it is presented by Aristotle in Posterior Analytics A.33. Aristotle's contrast is formulated in terms of understanding or not understanding some "necessary items". I claim that the contrast can only be understood in terms of explanatory relevance. The "necessary items" are middle terms (or explanatory factors) that are necessary for the fully appropriate explanation. This approach gives a coherent interpretation of each step in the chapter.

This paper explores Aristotle's remarks in Posterior Analytics on certain special disciplines that are subordinate to pure mathematical sciences. Optics, harmonics and mechanics prove their own contents by means of premises belonging to arithmetic or geometry. Even though subaltern sciences are exceptions to the prohibition on kind crossing, the premises to their demonstrations are legitimately appropriate to the relative conclusions. In order to delineate the demonstrative structure of subordinate sciences, Aristotle introduces the distinction between knowledge of a fact and knowledge (...) of the reason for it. In his view, these two different levels of knowledge, characterizing respectively empirical and theoretical approaches, are closely related. Nautical astronomy, for instance, deals with the observation and recording of the astral motions, which are made intelligible by mathematical astronomy. The Aristotelian ideal of an explanatory connection between appearances and mathematical principles seems to be the main aspect in the treatment of subordinate sciences in Posterior Analytics. (shrink)

Although he does not have an explicit theory of supposition as is found in the works of Latin medieval philosophers, Avicenna has two doctrines giving something equivalent: the threefold distinction of quiddity, corresponding to a division of simple, personal and material supposition, and his analyses of truth conditions for categorical propositions, where sentential context determines in part the reference of their terms. While he does address which individuals are being referred to by the universal terms used there, Avicenna concentrates more (...) on the varied temporal durations of the predications being made. In Western terms, he has incorporated ampliation and restriction into the theory of supposition itself. (shrink)

In Posterior Analytics 1.3, Aristotle advances three arguments against circular proof. The third argument relies on his discussion of circular proof in Prior Analytics 2.5. This is problematic because the two chapters seem to deal with two rather disparate conceptions of circular proof. In Posterior Analytics 1.3, Aristotle gives a purely propositional account of circular proof, whereas in Prior Analytics 2.5 he gives a more complex, syllogistic account. My aim is to show that these problems can be solved, and that (...) Aristotle’s third argument in 1.3 is successful. I argue that both chapters are concerned with the same conception of circular proof, namely the propositional one. Contrary to what is often thought, the syllogistic conception provides an adequate analysis of the internal deductive structure of the propositional one. Aristotle achieves this by employing a kind of multiple-conclusion logic. (shrink)

Does Duncan Kennedy successfully cannibalize jurisprudence? He attempts to do it by demonstrating the inexistence of rightness in legal argumentation. If there is no right legal argument, then there is no right answer in adjudication, adjudication is not a rational enterprise and legal doctrine cannot be said to be a science. It can be shown that skepticism is self-defeating. Duncan Kennedy can avoid self defeat only because he actually believes in a lot of legal arguments. His thesis that judges decide (...) questions of policy without any methodology that distinguishes them from legislators does not hold. Judicial reasoning is subject to constraints that do not affect legislators. It must be based on the sources of law and is limited by rules of procedure. Even when the judges have ‘interstitial’ legislative powers they are, unlike the legislator, bound to fit the system and their decisions are considered in procedure from the perspective of the right answer doctrine. The only work that can convincingly refute the skeptic argument against legal science is the reconstruction of jurisprudence as a scientific enterprise. Such work is beyond the scope of any single paper. The article aims to give some inspirations for such a task. (shrink)

En este artículo se discute la relación entre silogismo y demostración con respecto al concepto aristotélico del conocimiento científico formulado en los Analíticos segundos. La argumentación sigue tres líneas principales: (i) se ofrecen razones para rechazar la relegación de la sistematización silogística a la instancia postrera de justificación y exposición didáctica del conocimiento previamente adquirido. Como respuesta alternativa, (ii) se muestra que una explicación aristotélica necesita la silogística en virtud del papel que desempeña la causa como término medio silogístico. En (...) consecuencia, debería estar en condiciones de (iii) sostener que no resulta factible establecer firmemente los principios propios como premisas explicativas sin construir silogismos. This article focuses on the relation between syllogism and demonstration, as related to Aristotle's concept of scientific knowledge in his Posterior Analytics. Three main lines of argumentation are followed: (i) reasons are given to reject that syllogistic systematization plays a unique role as a skill for justification and didactic proof of a body of knowledge previously acquired. Alternatively, (ii) it is showed that an Aristotelian explanation requires syllogistic as to the role of cause as middle syllogistic term. Thus, it should be feasible (iii) to sustain that it is not possible to firmly establish proper principles as explanative premises without constructing syllogisms. (shrink)

From Euclid to the second half of the 17th century, mathematicians as well as philosophers continued to raise the question of the angle of contact and, generally, of the concept of angle. This article is the first essay devoted to this subject in Arabic mathematics. It deals with Greek writings translated into Arabic on the one hand, and contributions of Arabic mathematicians on the other hand: al-Nayrīzī, Ibn al-Haytham, al-Samawʾal, al-Shīrāzī, al-Fārisī, al-Qūshjī, among others. Most of these contributions are hitherto (...) unknown.Depuis Euclide jusque tard dans le xviie siècle, mathématiciens et philosophes n'ont cessé de s'interroger sur l'angle de contingence et, plus généralement, sur la notion d'angle. Cet article est le premier essai où sont examinés les écrits grecs portant sur ce thème et transmis en arabe, ainsi que les nombreux travaux, pour la plupart jusqu'ici inconnus, des mathématiciens arabes eux-mêmes: al-Nayrīzī, Ibn al-Haytham, al-Samawʾal, al-Shīrāzī, al-Fārisī, al-Qūshjī, entre autres.Send article to KindleTo send this article to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle. Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply. Find out more about the Kindle Personal Document Service.L'ANGLE DE CONTINGENCE: UN PROBLÈME DE PHILOSOPHIE DES MATHÉMATIQUESVolume 22, Issue 1Roshdi Rashed DOI: https://doi.org/10.1017/S0957423911000087Your Kindle email address Please provide your Kindle [email protected]@kindle.com Available formats PDF Please select a format to send. By using this service, you agree that you will only keep articles for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services. Please confirm that you accept the terms of use. Cancel Send ×Send article to Dropbox To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about sending content to Dropbox. L'ANGLE DE CONTINGENCE: UN PROBLÈME DE PHILOSOPHIE DES MATHÉMATIQUESVolume 22, Issue 1Roshdi Rashed DOI: https://doi.org/10.1017/S0957423911000087Available formats PDF Please select a format to send. By using this service, you agree that you will only keep articles for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services. Please confirm that you accept the terms of use. Cancel Send ×Send article to Google Drive To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about sending content to Google Drive. L'ANGLE DE CONTINGENCE: UN PROBLÈME DE PHILOSOPHIE DES MATHÉMATIQUESVolume 22, Issue 1Roshdi Rashed DOI: https://doi.org/10.1017/S0957423911000087Available formats PDF Please select a format to send. By using this service, you agree that you will only keep articles for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services. Please confirm that you accept the terms of use. Cancel Send ×Export citation Request permission. (shrink)

It has often been claimed that (i) Aristotle's expression 'protasis' means 'premiss' in syllogistic contexts and (ii) cannot refer to the conclusion of a syllogism in the Prior Analytics. In this essay we produce and defend a counter-example to these two claims. We argue that (i) the basic meaning of the expression is 'proposition' and (ii) while it is often used to refer to the premisses of a syllogism, in Prior Analytics 1.29, 45b4-8 it is used to refer to the (...) conclusion of a syllogism. In our view, the best explanation of Aristotle's use of the expression 'protasis' is that it means proposition throughout but is frequently used without change of meaning (in certain specific contexts) to refer to the premisses from which a conclusion follows. In Prior Analytics 1.29, 45b4-8 he uses 'protasis' to refer to the conclusion when he needs a single expression to refer to both the conclusion and one of the premisses of the syllogism that constitutes the core of a syllogism through the impossible. If we are correct, we have shown that the view that the expression 'the final protasis' in EN 7.3, 1147b9ff must mean 'the final premiss' and so cannot refer to the conclusion of the relevant syllogism is mistaken. (shrink)

Ao introduzir o estudo da substância em Metafísica Z1, Aristóteles apresenta um argumento cujo ponto inicial corresponde a uma questão acerca do estatuto ontológico de certos itens não-substanciais. Normalmente, entende-se que o objetivo desse argumento é estabelecer a compreensão da substância como ser primeiro. Pretende-se, aqui, propor uma interpretação alternativa para tal argumento. A questão acerca do estatuto ontológico de certos itens não-substanciais não teria o papel de estabelecer a compreensão da substância como ser primeiro, mas dirigir a investigação para (...) a razão pela qual a substância é tomada como ser primeiro. (shrink)

From Euclid to the second half of the 17th century, mathematicians as well as philosophers continued to raise the question of the angle of contact and, generally, of the concept of angle. This article is the first essay devoted to this subject in Arabic mathematics. It deals with Greek writings translated into Arabic on the one hand, and contributions of Arabic mathematicians on the other hand: al-Nayrīzī, Ibn al-Haytham, al-Samawʾal, al-Shīrāzī, al-Fārisī, al-Qūshjī, among others. Most of these contributions are hitherto (...) unknown.Depuis Euclide jusque tard dans le xviie siècle, mathématiciens et philosophes n'ont cessé de s'interroger sur l'angle de contingence et, plus généralement, sur la notion d'angle. Cet article est le premier essai où sont examinés les écrits grecs portant sur ce thème et transmis en arabe, ainsi que les nombreux travaux, pour la plupart jusqu'ici inconnus, des mathématiciens arabes eux-mêmes: al-Nayrīzī, Ibn al-Haytham, al-Samawʾal, al-Shīrāzī, al-Fārisī, al-Qūshjī, entre autres.Send article to KindleTo send this article to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle. Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply. Find out more about the Kindle Personal Document Service.L'ANGLE DE CONTINGENCE: UN PROBLÈME DE PHILOSOPHIE DES MATHÉMATIQUESVolume 22, Issue 1Roshdi Rashed DOI: https://doi.org/10.1017/S0957423911000087Your Kindle email address Please provide your Kindle [email protected]@kindle.com Available formats PDF Please select a format to send. By using this service, you agree that you will only keep articles for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services. Please confirm that you accept the terms of use. Cancel Send ×Send article to Dropbox To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about sending content to Dropbox. L'ANGLE DE CONTINGENCE: UN PROBLÈME DE PHILOSOPHIE DES MATHÉMATIQUESVolume 22, Issue 1Roshdi Rashed DOI: https://doi.org/10.1017/S0957423911000087Available formats PDF Please select a format to send. By using this service, you agree that you will only keep articles for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services. Please confirm that you accept the terms of use. Cancel Send ×Send article to Google Drive To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about sending content to Google Drive. L'ANGLE DE CONTINGENCE: UN PROBLÈME DE PHILOSOPHIE DES MATHÉMATIQUESVolume 22, Issue 1Roshdi Rashed DOI: https://doi.org/10.1017/S0957423911000087Available formats PDF Please select a format to send. By using this service, you agree that you will only keep articles for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services. Please confirm that you accept the terms of use. Cancel Send ×Export citation Request permission. (shrink)

Abstract In Posterior Analytics II.19 Aristotle raises and answers the question, how do first principles become known? The usual view is that the question asks about the process or method by which we learn principles and that his answer is induction. I argue that the question asks about the original prior knowledge from which principles become known and that his answer is perception. Hence the aim of II.19 is not to explain how we get all the way to principles but (...) to defend the claim that our knowledge of them originates in perception. Aristotle explains how we learn principles earlier in book II, in his account of definitional inquiry. In II.19 he explains how we reach by induction the preliminary accounts necessary for such inquiries. (shrink)

At the end of Republic 5, Plato distinguishes epistêmê from doxa, knowledge from belief. In Posterior Analytics 1.33, Aristotle provides his own distinction between epistêmê and doxa. I explore his way of distinguishing them and compare it with Plato's.

As Aristotle himself says, A.Po. 2.13 is an attempt to provide some rules to hunt out the items predicated in what something is, namely to discover definitions. Since most of this chapter is devoted to the discussion of some rules of division , it may be inferred that somehow division plays a central role in the discovery of definitions. However, in the following pages I shall not discuss what this role is. Nor shall I discuss what place division has in (...) the wider discussion of definition and explanation as it emerges from A.Po. 2. 1 shall rather focus on the argument that Aristotle reports and discusses in A.Po. 2.13.97a6–22, and which our extant sources ascribe to Speusippus. As will become clear later on, this argument undermines the possibility of giving any definition, and Aristotle deals with it here because he can block it by exploiting some properties of the method of division. (shrink)

The Regress: Knowledge, we like to suppose, is essentially a rational thing: if I claim to know something, I must be prepared to back up my claim by statingmy reasons for making it;and if my claim is to be upheld, my reasons must begood reasons. Now suppose I know that Q; and let my reasons be conjunctively contained in the proposition that R. Clearly, I must believe that R ;equally clearly, I must know that R . Thus if I know (...) that Q, I know that R. But if I know that R, then I must have my reasons, R' for holding R; and, by the same argument, I mustknow that R'. And if R', then R”; and so on, ad infinitum. (shrink)

‘There are important differences between Aristotle's account of homonymy and synonymy on the one hand, and Speusippus' on the other; in particular, Aristotle treated homonymy and synonymy as properties of things, whereas Speusippus treated them as properties of words. Despite this difference, in certain significant passages Aristotle fell under the influence of Speusippus and used die words “homonymous” and “synonymous” in their Speusippan senses.’.

A predicate logic typically has a heterogeneous semantic theory. Subjects and predicates have distinct semantic roles: subjects refer; predicates characterize. A sentence expresses a truth if the object to which the subject refers is correctly characterized by the predicate. Traditional term logic, by contrast, has a homogeneous theory: both subjects and predicates refer; and a sentence is true if the subject and predicate name one and the same thing. In this paper, I will examine evidence for ascribing to Aristotle the (...) view that subjects and predicates refer. If this is correct, then it seems that Aristotle, like the traditional term logician, problematically conflates predication and identity claims. I will argue that we can ascribe to Aristotle the view that both subjects and predicates refer, while holding that he would deny that a sentence is true just in case the subject and predicate name one and the same thing. In particular, I will argue that Aristotle's core semantic notion is not identity but the weaker relation of constitution. For example, the predication ‘All men are mortal’ expresses a true thought, in Aristotle's view, just in case the mereological sum of humans is a part of the mereological sum of mortals. (shrink)

The problem. The purpose of this paper is to provide a general discussion of Aristotle's views on scientific explanation, by which I mean a discussion of Aristotle's treatment of scientific explanation, its structure and its principles, as distinct from Aristotle's own principles of explanation. By means of this distinction I hope to be excused from a discussion of Aristotle on form and matter, potentiality and actuality, and the four causes, and to avoid so far as possible the controversy among commentators (...) concerning the respective merits of Aristotlequanaturalist and Aristotlequapre-Thomist Thomist. I wish to be excused from treating these problems in order to approach directly Aristotle's formal treatment of scientific explanation as given in thePosterior Analytics, but if I were to be accused of introducing a distinction between parts of the Aristotelian corpus for which there is insufficient warrant, if I were told that I am making an illegitimate abstraction from the whole of which thePosterior Analyticsis but a part, I should plead not guilty. (shrink)

There is agreement neither concerning the point that is being made in Posterior analytics 96b15–25 nor the issue Aristotle intends to address. There are two major lines of interpretation of this passage. According to one, sketched by Themistius and developed by Philoponus and Eustratius, Aristotle is primarily concerned with determining the definitions of the infimae species that fall under a certain genus. They understand Aristotle as arguing that this requires collating definitional predictions, seeing which are common to which species. Pacius, (...) on the other hand, takes Aristotle to be saying that a genus is studied scientifically through first determining the infimae species that fall under that genus. This interpretation attributes to Aristotle a distinction between primary and derivative subjects. I argue for Pacius’s interpretation, defending it against Barnes’s objections.Author Keywords: Demonstration; Definition; Aristotle; Species; Principles. (shrink)

Fred's semantics for McCall's syntactic presentation of Aristotle's assertoric and apodeictic syllogistic is altered to free it from Thom's objections that it is unAristotelian. The altered semantics rejects Baroco-XLL and Bocardo-LXL, which Thom says Aristotle should have accepted. Aristotle's proofs that use ecthesis are formalized by using singular sentences. With one exception the (acceptance) axioms for McCall's system L-X-M are derivable. Formal proofs are shown to be sound.

This is a brief note that looks at the problem presented by the traditional rendering of the modal syllogism Disamis XLL. In two recent articles, I argue that we should not attribute Disamis XLL to Aristotle. The purpose of this note is to provide textual support for my claim.

The taxonomy and analysis of fallacies in Aristotle's Sophistical Refutations pre-date the formal logic of his Prior Analytics A4-6. Of the 64 fully described examples of ?sophistical refutations? which are fallacious because they are only apparently valid, 49 have the wrong number of premisses or the wrong form of premiss or conclusion for analysis by the Prior Analytics theory of the categorical syllogism. The rest Aristotle either frames so that they do not look like categorical syllogisms or analyses in a (...) quite different way than by categorical syllogistic. (shrink)

Ever since ?ukasiewicz, it has been opinio communis that Aristotle's modal syllogistic is incomprehensible due to its many faults and inconsistencies, and that there is no hope of finding a single consistent formal model for it. The aim of this paper is to disprove these claims by giving such a model. My main points shall be, first, that Aristotle's syllogistic is a pure term logic that does not recognize an extra syntactic category of individual symbols besides syllogistic terms and, second, (...) that Aristotelian modalities are to be understood as certain relations between terms as described in the theory of the predicables developed in the Topics. Semantics for modal syllogistic is to be based on Aristotelian genus-species trees. The reason that attempts at consistently reconstructing modal syllogistic have failed up to now lies not in the modal syllogistic itself, but in the inappropriate application of modern modal logic and extensional set theory to the modal syllogistic. After formalizing the underlying predicable-based semantics (Section 1) and having defined the syllogistic propositions by means of its term logical relations (Section 2), this paper will set out to demonstrate in detail that this reconstruction yields all claims on validity, invalidity and inconclusiveness that Aristotle maintains in the modal syllogistic (Section 3 and 4). (shrink)

One semantic and two syntactic decision procedures are given for determining the validity of Aristotelian assertoric and apodeictic syllogisms. Results are obtained by using the Aristotelian deductions that necessarily have an even number of premises.

(1993). Alexander of aphrodisias and others on a controversial demonstration in aristotle’s modal syllogistic. History and Philosophy of Logic: Vol. 14, No. 2, pp. 201-214.

Three distinctly different interpretations of Aristotle’s notion of a sullogismos in Prior Analytics can be traced: (1) a valid or invalid premise-conclusion argument (2) a single, logically true conditional proposition and (3) a cogent argumentation or deduction. Remarkably the three interpretations hold similar notions about the logical relationships among the sullogismoi. This is most apparent in their conflating three processes that Aristotle especially distinguishes: completion (A4-6)reduction(A7) and analysis (A45). Interpretive problems result from not sufficiently recognizing Aristotle’s remarkable degree of metalogical (...) sophistication to distinguish logical syntax from semantics and, thus, also from not grasping him to refine the deduction system of his underlying logic. While it is obvious that Aristotle most often uses ‘sullogimos’ to denote a valid argument of a certain kind, we show that at Prior Analytics A4-6, 7, 45 Aristotle specifically treats a sullogismos as an elemental argument pattern having only valid instances and that such a pattern then serves as a rule of deduction in his syllogistic logic. By extracting Aristotle’s understanding of three proof-theoretic processes, this paper provides new insight into what Aristotle thinks reasoning syllogistically is and, moreover, it resolves three problems in the most recent interpretation that takes a sullogismos to be a deduction. (shrink)

This dissertation explores Aristotle’s use of teleology as a principle of explanation, especially as it is used in the natural treatises. Its main purposes are, first, to determine the function, structure, and explanatory power of teleological explanations in four of Aristotle’s natural treatises, that is, in Physica (book II), De Anima, De Partibus Animalium (including the practice in books II-IV), and De Caelo (book II). Its second purpose is to confront these findings about Aristotle’s practice in the natural treatises with (...) the theoretical picture of the structure of teleological explanations gained from Aristotle’s theory of scientific demonstration. For this purpose a new interpretation of Analytica Posteriora II.11 is presented. This study thereby contributes to recent scholarship on the relation between Aristotle’s philosophy of science and his philosophy of nature, while at the same time adding to our knowledge of Aristotle’s notion of teleology in terms of its explanatory merits and limits. (shrink)

Modern logicians have sought to unlock the modal secrets of Aristotle's Syllogistic by assuming a version of essentialism and treating it as a primitive within the semantics. These attempts ultimately distort Aristotle's ontology. None of these approaches make full use of tests found throughout Aristotle's corpus and ancient Greek philosophy. I base a system on Aristotle's tests for things that can never combine (polarity) and things that can never separate (inseparability). The resulting system not only reproduces Aristotle's recorded results for (...) the apodictic syllogistic in the Prior Analytics but it also generates rather than assumes Aristotle's distinctions among 'necessary', 'essential' and 'accidental'. By developing a system around tests that are in Aristotle and basic to ancient Greek philosophy, the system is linked to a history of practices, providing a platform for future work on the origins of logic. (shrink)

The paper rejects Michael Wolff's claim that Aristotle offers proofs for the validity of his perfect syllogisms.

In an earlier article (see J Gen Philos Sei (2010) 41: 341-355) I have compared Aristotle's syllogistic with Kant's theory of "pure ratiocination". "Ratiocinia pura" („reine Vernunftschlüsse") is Kant's designation for assertoric syllogisms Aristotle has called 'perfect'. In Kant's view they differ from non-pure ratiocinia precisely in that their validity rests only on the validity of the Dictum de omni et nullo (which, however, in Kant's view can be further reduced to more fundamental principles) whereas the validity of non-pure ratiocinia (...) additionally presupposes the validity of inferences which Kant calls consequentiae immediatae. I have argued that Kant's view is in some (not in all) essential features in accordance with Aristotle's view concerning perfect syllogisms and certainly leading to a tenable and interesting logical theory. As a result I have rejected not only the interpretation of Aristotle adopted by Theodor Ebert, but also the objections he has raised against Kant's logical theory. As far as Aristotle is concerned, Ebert has attempted to defend his position in the first part of his reply to my article published in J Gen Philos Sei (2009) 40: 357-365, and I have argued against this defence in issue 1 of the J Gen Philos Sei (2010) 41: 199-213 (cf. Ebert's answer in the same issue pp. 215-231). In the following discussion I deal with Eberts defence of his criticism of Kant published in the second part of his reply to my article (see J Gen Philos Sei (2009) 40: 365-372). I shall argue, that Kant's principle 'nota notae est nota rei ipsius' and his use of technical vocabulary stand up to the objections raised by Ebert. His attempts to prove that Kant's logical theory is defective are based on several misinterpretations. (shrink)

Aristotle's notion of experience plays an important role in his epistemology as the link between perception and memory on the one side, and higher cognitive capacities on the other side. However, Aristotle does not say much about it, and what he does say seems inconsistent. Notably, some passages suggest that it is a non-rational capacity, others that it is a rational capacity and that it provides the principles of science. This paper presents a unitary account of experience. It explains how (...) experience grows from perception and memory into a rational capacity, and in what way it provides the principles. (shrink)

Logic is usually thought to concern itself only with features that sentences and arguments possess in virtue of their logical structures or forms. The logical form of a sentence or argument is determined by its syntactic or semantic structure and by the placement of certain expressions called “logical constants.”[1] Thus, for example, the sentences Every boy loves some girl. and Some boy loves every girl. are thought to differ in logical form, even though they share a common syntactic and semantic (...) structure, because they differ in the placement of the logical constants “every” and “some”. By contrast, the sentences Every girl loves some boy. and Every boy loves some girl. are thought to have the same logical form, because “girl” and “boy” are not logical constants. Thus, in order to settle questions about logical form, and ultimately about which arguments are logically valid and which sentences logically true, we must distinguish the “logical constants” of a language from its nonlogical expressions. (shrink)

In Aristotle's biological works, there is an apparent conflict between passages which seem to insist that only hypothetical necessity (anagk ex hypotheses) operates in the sublunary world, and passages in which some biological phenomena are explained as simply (hapls) necessary. Parallel to this textual problem lies the claim that explanations in terms of simple necessity render teleological explanations (in some of which Aristotle puts hypothetical necessity to use) superfluous. I argue that the textual conflict is only apparent, and that Aristotle's (...) notion of coincidental sameness allows him to avoid the superfluity problem. (shrink)

In Eudemian Ethics I 6, Aristotle describes the progress of the ethical investigation as a drift from a) what is true but not clarifying to b) what is true and clarifying. The drift from a) to b) is usually interpreted as the overcome of a first obscure and confused grasp of the subject by a more accurate and reliable account. In this paper, I claim that the understanding of the methodological role of a) depends upon its dissociation from the notions (...) of obscurity and confusion. What is true but not clarifying should be rather understood as a first indistinct (but not confused) grasp of the subject. Its insuficiency as regards explanation is to be accounted on the base of its indistinctness and not on its supposed obscurity. (shrink)