The paper discusses the active part in the process of perceiving, usually expressed by the Greek word krinein. It is argued that krinein in one of its uses means "to judge" in the sense of judging a case, i. e. deciding it. It is not used for making statements. A second meaning of the Greek word is that of discerning or discriminating, and it is this meaning that plays a central part in Aristotle's theory of perception.

The question as to what makes a perfect Aristotelian syllogism a perfect one has long been discussed by Aristotelian scholars. G. Patzig was the first to point the way to a correct answer: it is the evidence of the logical necessity that is the special feature of perfect syllogisms. Patzig moreover claimed that the evidence of a perfect syllogism can be seen for Barbara in the transitivity of the a-relation. However, this explanation would give Barbara a different status over the (...) other three first figure syllogisms. I argue that, taking into account the role of the being-contained-as-in-a-whole formulation, transitivity can be seen to be present in all four first figure syllogisms. Using this wording will put the negation sign with the predicate, similar to the notation in modern predicate calculus. (shrink)

This is a German translation with commentary of Aristotle’s Prior Analytics, Book I. The introduction (‚Einleitung‘, pp. 97–182) contains a concise history of the reception of Aristotle’s syllogistic from Theophrastus to Kant and Hegel. The commentary places special attention to the modal chapters (i. e. I 3 and 8–22). Aristotle’s modal syllogistic is treated with more sympathy than in other modern commentaries and discussions of this part of Aristotle’s logic.

I argue, firstly, that the accounts of 'accident' in Aristotle's Met. V 30 and in Top. I 5 cannot be used to elucidate each other: the Metaphysics passage tries to disentangle the uses of a Greek word, the Topics passage introduces technical terms for Aristotle's semantics. I then argue that the positive definition in Top. I 5 is to be understood in the following way: X is an accident of Y iff X belongs to Y and if there is a (...) Z such that X can belong to Z and also not belong to Z. Thus, being white is an accident of snow. I finally argue that certain shortcomings in the Topics account lead Aristotle to redefine accident in the Posterior Analytics. (shrink)

This monograph discusses the sources for ancient propositional logic, mainly in Sextus Empiricus and Diogenes Laertius bk. VII. It is argued that most of the sources in Sextus which have hitherto been taken to be sources for Stoic logic either do not report Stoic logic at all or report pre-Chrysippean Stoic logic. These texts report (in the first case) a group labelled the Dialecticians whose most prominent members were Diodorus Cronus and Philo or else (in the second case) early Stoic (...) logicians heavily influenced by the Dialecticians. The texts discussed concern the theory of signs, the theory of proof and the classifications of propositions and of arguments. (shrink)

Kant’s Categorical Imperative (CI) is to be taken as a necessary and sufficient condition for any action that is permissible, i. e. not prohibited. The class of permissible actions contains actions which are allowed as well as those which are morally required. If to perform an action and to abstain from this action can be taken to be ‘practical opposites’, then an action that is morally required for, a duty, is an action whose practical opposite is prohibited, and vice versa. (...) The class of actions which are merely allowed (neither prohibited nor morally required for) contains all and only those actions who together with their practical opposites belong to the class of permissible (not prohibited) actions. The paper then adduces passages from Kant’s ethical writings on the CI supporting these distinctions. (shrink)

It is argued that recollection in Plato's "Meno" is used as a metaphor, though not one for a priori knowledge: the point of comparison is the analogy between the processes of learning in the sense of coming to know from an error and recollecting something one has forgotten. Recollecting in this sense as well as correcting an error implies the becoming aware of a lack of knowledge previously unnoticed. It is shown that the geometry lesson (82b9-85b7) is intended to bring (...) out this analogy. It is argued further that the error to be corrected by the staging of the geometry lesson is an error of Meno's concerning the nature of knowledge. It is finally argued that Socrates' speech in 81a5-d5 is a parody of a Gorgian speech and that the learning-is-recollection statement in this passage is an allegorical conceit in the manner of Gorgias and Empedocles. (shrink)

"Der vorliegende Band vereinigt die Beitrèage des Symposiums zur Logik der Stoiker und ihrer Vorlèaufer, das vom 1.-7.9.1991 in Bamberg stattfand"--P. [7].

This paper discusses the reports in Diogenes Laertius and in Sextus Empiricus concerning the classification of propositions. It is argued that the material in Sextus uses a source going back to the Dialectical school whose most prominent members were Diodorus Cronus and Philo of Megara. The material preserved in Diogenes Laertius, on the other hand, goes back to Chrysippus.

I try to show that Aristotle does not restrict 'praxis' to those activities which have their end in themselves. NE VI 5, 1140b6-7 need not to be taken as an argument in favour of the restricted interpretation: the wording of the passage is compatible with the interpretation that the end of a praxis is (another) praxis (e.g. eupraxia), the end of a poiesis on the other hand is never a poiesis. This interpretation fits better the use of 'praxis' throughout the (...) NE. MM A 34, 1197a4-12 is discarded since the MM is not written by Aristotle. Next I discuss the relation between the verbs 'prattein' and 'poiein' on the one hand and the corresponding nouns 'poiesis' and 'praxis' on the other, in order to determine their exact meaning. To conclude, Aristotle's distinctions are compared to certain tenets of H. Arendt in her 'Vita Activa'. (shrink)

The paper discusses Timaeus 27d5-29b1, i.e. part of the proem of Timaeus' lecture. This passage contains the exposition of three principles (27d5-28b2) and their application to certain questions intended to lay the foundations for the subsequent cosmology (28b2-29b1). I argue that one of the main results Timaeus wants to deduce from his principles, i.e. the claim that the cosmos has been constructed by a divine craftsman, is not warranted by his principles and rests on a rather conspicuous flaw in the (...) argument. I further discuss the question whether this mistake should be attributed to Plato or whether Plato deliberately has Timaeus commit this mistake; I argue for the second alternative. (shrink)

This paper (1) criticizes Patzig's explanation of Aristotle's reason for calling his first figure syllogisms perfect syllogisms, i.e. the transitivity relation: it can only be used for Barbara, not for the other three moods. The paper offers (2) an alternative interpretation: It is only in the case of the (perfect) first figure moods that we can move from the subject term of the minor premiss, taken to be a predicate of an individual, to the predicate term of the major premiss. (...) This contention is supported (i) by Aristotle's wording of the dictum de omni et nullo and (ii) by Aristotle's use of a formula which puts the minor term in the first position when he first states Barbara and Celarent. (shrink)

In this paper I defend the existence of a Dialectical school proper against criticisms brought forward by Klaus Döring and by Jonathan Barnes. Whereas Döring claims that there was no Dialectical school separate from the Megarians, Barnes takes issue with my claim (argued for in “Dialektiker und frühe Stoiker bei Sextus Empiricus”) that most of the reports in Sextus on the dialecticians refer to members of the Dialectical school. Barnes contends that these dialecticians are in fact Stoic logicians. As against (...) Döring, I argue that the passage in Diogenes Laertius II 113 (first drawn attention to by David Sedley) which talks of a the Megarian Stilpo winning over disciples from the Dialecticians is not refuted by Döring’s arguments. It clearly shows that the Dialecticians and the Megarians at the time were taken to be different philosophical sects. As against Barnes I insist on the differences between the report in Ps.-Galen’s Historia 9 and the Sextan report on the theory of sign in AM VIII. These reports offer incompatible definitions of the indicative sign. Moreover, the classification of simple propositions reported by Sextus at AM VIII 96f. cannot be a truncated version of the (Stoic) list to be found in Diogenes Laertius VII 69f. since in Sextus’ report one of the three classes of simple propositions is labelled middle (meson). This is a certain sign that we are dealing with a triad, and hence that this list is meant to be complete. Therefore the classification found in Sextus and attributed to the dialecticians and the one in Diogenes Laertius reporting Stoic material do come from different sources. (shrink)

The paper discusses Habermas` contribution to a debate between him and Joseph Ratzinger, at the time the prefect of the Congregation for the Catholic faith. Habermas is criticized for his tendency to adopt openly anti-enlightenment positions.

This is a reply to Vincent Carraud/René Verdon « Remarques circonspectes sur la mort de Descartes » (published in Revue du dix-septième siècle, n° 265, 2014/4, pp. 719-726, online: http://www.cairn.info/revue-dix-septieme-siecle-2014-4-page-719.htm, containing a critique of my "L'énigme de la mort de Descartes" Paris, 2011). I discuss the fatal illness and the death of Descartes, arguing that Descartes was very probably the victim of arsenical poisoning. The suspected murderer is a French priest, François Viogué, living with Descartes in 1650 at the French (...) embassy in Stockholm who may have seen in Descartes an obstacle to the hoped for conversion of queen Christina of Sweden. As against Carraud/Verdon I stress the medical facts, in particular the fact that Descartes himself seems to have suspected poisoning, since he asked for an emetic shortly before his death. (shrink)

I contend that “philosophos” is meant to carry the connotation of a Pythagorean: Euenus is a native from Paros which had a strong Pythagorean community down to the end of the fifth century. Moreover, “philosophos” was used to refer to the Pythagoreans, as can be seen from the story related by Cicero from Heraclides Ponticus (Tusc. Disp. V, iii, 7-8; cp. DL, 1.12; 8.8). I argue (against Burkert) that even if this story is part of the lore surrounding Pythagoras and, (...) hence, without historical value as for Pythagoras, it may still be used as evidence for the use of “philosophos” among latter-day Pythagoreans. (shrink)

In this paper I argue that the Stoic theory of signs as reported by Sextus Empiricus in AM and in PH belongs to Stoic logicians which precede Chrysippus. I further argue that the PH-version of this theory presupposes the version in AM and is an attempt to improve the older theory. I tentatively attribute the PH-version to Cleanthes and the AM-version to Zeno. I finally argue that the origin of this Stoic theory is to be found in the Dialectical school (...) (probably Philo of Megara) whose theory of signs has been preserved in Pseudo-Galen, Historia philosopha cap. 9. (shrink)

The paper starts from a distinction between two terms in Aristotle: kategoroumenon and kategoria. It is argued that the job of the first is to pick out 'predicated predicates' (i.e. predicates attached to a specific subject), the job of the second is to designate 'predicable predicates' (terms which can be attached to specific subjects). It is then argued (1) that Aristotle's division of the (erroneously) so-called 'predicables' (i. e. genus, proprium, definiens, accident) is a classification of predicated predicates, (2) that (...) the list of the "genera of kategoriai" in Top. I 9 which starts with ti estin (essence) as its first member contains a classification of predicable predicates, and (3) that the list in Cat. 4 (starting with ousia, 'substance') is a classification not of kategoriai, but of things there are. (shrink)

The reason for Aristotle’s treatment of (traditional) fourth figure syllogisms as first figure syllogisms with inverted terms in the conclusion is the following: To disprove the conclusiveness of a premiss pair Aristotle formulates two triplets of true propositions such that two of them correspond to the premiss pair in question and that the third proposition corresponding to a conclusion is an a-proposition in the first case, an e-proposition in the other. Since the truth of an a-proposition grants the falsity of (...) the contrary e- and of the contradictory o-proposition, the first triplet offers two counter-instances for invalid syllogisms with true premisses and false conclusions. Similarly the true e-proposition grants the falsity of an a- and an i-conclusion. Since an a-proposition can be converted to an i-proposition and an e-proposition is equivalent to its converse, these first figure triplets also disprove any first figure syllogism with converted conclusions, with the exception of o-conclusions. The invalidity of the latter ones, however, can be shown by using premiss conversions of (invalid) second and third figure syllogisms. The proposed explanation also makes clear why there are no rejection proofs for invalid syllogisms of (traditional) fourth figure syllogisms in the Analytics. (shrink)

This paper discusses the question why the first edition of Descartes' Meditations carries a title announcing a proof of the immortality of the soul, whereas Descartes himself (in the Synopsis as well as in his Replies) explicitly denies any intention to deliver such a proof. In the first part of the paper, I refute existing attempts to explain this inconsistency. In the second part, I argue that it was Descartes' intention to announce a proof for the immaterialitas, not for the (...) immortalitas of the soul, and that the first of these two words has been misread, probably by the Paris printer, and turned into immortalitas. I first adduce as evidence a remark by Baillet in his second (abbreviated) version of Descartes' biography, a remark that has hitherto gone unnoticed in the learned literature. (Baillet explicitly states, using French words indeed, that immortalitas/immortalité was put instead of immaterialitas/immaterialité.) I secondly point to three statements by Descartes concerning either the Meditations or the content of metaphysics generally; Descartes mentions the immateriality of the soul on all three occasions. -/- . (shrink)

In an earlier article (see J Gen Philos Sci (2009) 40: 357-372) I have discussed the arguments brought forward by Michael Wolff against the interpretation given in the commentary by Ebert and Nortmann on Aristotle's syllogistic theory (Aristoteles Analytica Priora Buch I, übersetzt und erläutert von Theodor Ebert und Ulrich Nortmann. Berlin 2007) and against the critique of Kant's adaption of the syllogistic logic. I have dealt with Wolff's arguments concerning (Ebert/Nortmann's interpretation of) Aristotle in the (...) paper mentioned and with his attempts to defend his critique in this subsequent article (part 1; see J Gen Philos Sci (2010) 41: 215-231). Part 2 (the paper below) is concerned with Wolffs renewed attempts to defend Kant as a logician. In particular I point out that if, as Wolff claims, the nota notae relation in Kant is restricted to subordinated concepts, then it can hardly serve as a principle for syllogistic logic, as Kant claims. Against Wolff's attempts to defend Kant's claim that o-propositions are simpliciter convertible, I point out two arguments: (1) Even if Kant, following the Vernunftlehre by Meier, has assumed that an o-proposition can be turned into an i-proposition (by adding the negation sign to the predicate), this conversion is useless for the reduction to first figure syllogisms since we are no longer dealing with three syllogistic terms but with four. (2) It is quite unlikely that Kant has a conversion of this type in mind since the texts of his students always talk of the group of either the particular propositions or else of the negative propositions. Given Kant's mistakes concerning the convertibility simpliciter of o-propositions, it is no wonder that he overlooks the special status of the moods Baroco and Bocardo. Wolffs attempts to provide Kant with what he claims are direct proofs for these moods can be shown to rely on a reductio ad impossibile. Kant mistook what are parts of the proofs for the validity of moods in figures two to four as parts of these moods themselves. Wolff—who tries to defend Kant on this point—is forced to an artificial and unconvincing reading of the Kantian texts. (shrink)

Why does Aristotle not use the copulative wording for categorical propositions, but instead the clumsier terminological formulations (e. g. the B belongs to every A) in his syllogistic? The proposed explanations by Alexander, Lukasiewicz and Patzig: Aristotle wants to make clear the difference between subject and predicate, seems to be insufficient. In quantified categorical propositions, this difference is always sufficiently clear by the use of the pronouns going with the subject expressions. Aristotle opts for the terminological wording because in premiss (...) pairs of figures two and three he can thus suppress the middle term in one of the premisses and connect the major and minor term, using connecting particles. This renders the syllogisms more transparent. Had he used the copulative wording instead, he would have run into difficulties, in particular with o-propositions among the premisses (i. e. in Baroco and Bocardo) because in these cases the pronoun expressing the quantification would have to go with the subject term, the negation with the predicate. (shrink)

The paper gives an overall view of the history of the Stoa and its main achievements.

Der Artikel enthält eine Metakritik an einer von Vertretern der 'Erlanger Schule' vorgebrachten Kritik der Wissenschaftstheorie des Kritischen Rationalismus Poppers und Alberts. Von Janich/Kambartel/Mittelstraß war behauptet worden, das bei der Frage der Begründung wissenschaftlicher Sätze auftretende Trilemma von unendlichem Regreß, Zirkelschluß und axiomatischer Grundlegung beruhe auf einem "höchst eingeschränkten Verständnis von Begründung" und könne durch den Begriff der Verteidigung bzw. Verteidigbarkeit von Behauptungssätzen aufgelöst werden. Es wird gezeigt, daß die Auflösung dieses Trilemmas nur vermeintlich ist, weil sie auf einer unzulässigen (...) Änderung der Beweislastregelung beruht. (shrink)

The paper takes up a proposal made in 1936 by Guido Calogero concerning Parmenides 8.34-41 DK. According to Calogero, these verses should be placed behind 8.52 DK. Calogero's conjecture has gone unnoticed in the bulk of the Parmenides literature. I defend this transposition, partly enlarging Calogero's arguments, and discuss the philosophical implications of moving this text to the beginning of the doxa part of Parmenides' poem.

This is a collection of papers already published (spanning the years from 1976 to 1998) covering Aristotle’s logic, his theory of science, his psychology, and his Ethics. Three papers are in English, six in German. The book contains an index of proper names as well as a list of Ebert’s publications up to 2002.

This is a collection of papers already published (spanning the years from 1976 to 2002) covering mostly the history of philosophy, with the exception of Aristotle (papers on Aristotle are contained in vol. I). The bulk of the papers (eight) are on Plato (on the Meno, Phaedo, Republic and Sophist), two concern the Presocratics, one paper discusses the theory of sign with the Stoics, five are on modern philosophy (Descartes, Spinoza, Leibniz and Kant). Two papers are in English, the rest (...) in German. The book contains an index of proper names as well as a list of Ebert’s publications up to 2002. (shrink)

This paper argues that Plato’s Meno does not offer evidence for a belief, commonly attributed to Plato, that we when learning something recollect what we learn from previous existences. This “theory of recollection” is a construct based on a reading of the relevant passages in the Meno which does not take into account the dialectical aspect of Socrates’ discussion with his interlocutor. And in one passage (81e3) it is based on a variant reading for which a better and better attested (...) reading is available. The reference to recollection is used to make Meno agree to an absurd position. (shrink)

The article discusses the biographical and doxographical evidence for Diodorus Cronus, a prominent and influential figure at the start of Hellenistic philosophy. Special emphasis is given to Diodorus’ logic, as well to his controversy with Philo the Dialectician over the truth-criteria for the conditional as to his Master argument, concerning modal notions.

In this paper I argue for a reading of the Phaedo which takes into account the different levels of understanding and the different intentions of the partners to the dialectical discussions. Taking as an instantiation the argument about recollection, I show that the steps leading to the conclusion of the soul’s prenatal knowledge are steps to which Socrates’ interlocutor Simmias is committed; Socrates the questioner, however, does not commit himself to the concessions elicited from his partner.

I discuss the "theory of recollection" in Plato's Meno (81a–86c). Socrates' comments on the "geometry lesson" (85b8–86c3) are used to support the claim that, in a Socratic dialogue, we ought to differentiate between between non-committal and committal questions (= those implying a commitment of the questioner). It is then argued that the "theory of recollection" is no Platonic doctrine: Socrates uses Pythagorean material against Meno who is acquainted with the Pythagorean tradition and whose eristical argument against the possibility of learning (...) is meant to be refuted by the paradoxical consequences about the slave-boy's learning Meno is made to admit. (shrink)

[The discussion of Descartes’ death continues].

This monograph discusses the illness and death of René Descartes. All the hitherto available documents on his illness and death are collected in the appendix, partly also in the orginal French or Latin. These documents make it rather unlikely that Descartes died of pneumonia, the circumstances of his death suggest a poisoning by arsenic. The possible murderer and his motives are also discussed.

In this paper I argue that Leibniz' (L.) concept of entelechy, though L. himself believes to have derived it directly from Aristotle, does not correspond exactly to the Aristotelian concept. The main difference between the Aristotelian and the Leibnizian concept may be explained as follows: Whereas Aristotle uses "entelecheia" to designate a property possessed by living organisms, L. takes it to be a generic term for souls and other monads. It is further argued that Aristotle's somewhat intricate argument in De (...) Anima II 1 has contributed to the misunderstanding of the Aristotelian term, a misunderstanding starting already with the Aristotelian commentators Themistius, Philoponus and Simplicius. L. took his concept from the tradition of the commentators which he knew through the Italian humanist Ermolao Barbaro. (shrink)

In this paper, I take my start from certain distinctions Aristotle made use of in his analysis of prudence (phronesis) in the Nicomachean Ethics, but I then move away from Aristotle’s claims, in particular because I find fault with Aristotle’s exclusion of technical achievements from the realm of prudence. It is not the type of action which serves as a criterion to differentiate prudent acts from merely skilful ones, since in building a house you may act skilfully as well as (...) prudently; yet whereas in acting skilfully you look not farther than to the intended aim of the action, in acting prudently you take options and possible aims into account which are beyond the aim of the actual action. (shrink)

The book is a translation of my "Der rätselhafte Tod des René Descartes" (2009). It contains a rather complete collection of the documents on the fatal illness and the death of Descartes. It claims that the medical documents make a poisoning by arsenic very probable. The suspected murderer is the French monk Francois Viogué. His motive: Descartes was seen as a probable hindrance to the conversion of the Swedish queen Christina.

This is a French translation (with certain alterations) of my paper of 1995 on the question of the perfect syllogism.

Die hier vorliegende Neuübersetzung von Platons Menon enthält eine ausführliche Einführung, in der die Umstände der Abfassung, die möglichen Adressaten, die Figuren des Dialogs sowie dessen Thema und Fragestellung erörtert werden. Die Übersetzung beruht auf dem griechischen Text von Bluck. Daher sind in dem reproduzierten griechischen Text die Änderungen eingearbeitet, die sich aus dem Text von Bluck ergeben. Darüber hinaus werden an einer Reihe von Stellen Änderungen für den griechischen Text vorgeschlagen, teils aufgrund eigener oder fremder Konjekturen, teils aufgrund anderer (...) Lesarten in den Handschriften, von denen einige auch für das philosophische Verständnis des Dialogs von Bedeutung sind. Die Erläuterungen legen zum einen Wert auf eine genaue Analyse der Argumente des Gesprächs, zum anderen auf die literarischen Aspekte. Hierbei sprechen die Bezüge zu sizilischen Autoren zusammen mit den an die Komödie erinnernden Elementen dafür, dass Platon bei der Abfassung ein sizilisches Publikum vor Augen hatte. Aus diesen Voraussetzungen ergibt sich ein neues Verständnis verschiedener Positionen, die diesem Dialog zugeschrieben werden. (shrink)