Hermann Cohen’s essay on Maimonides’ ethics is one of the most fundamental texts of twentieth-century Jewish philosophy, correlating Platonic, prophetic, Maimonidean, and Kantian traditions. Almut Sh. Bruckstein provides the first English translation and her own extensive commentary on this landmark 1908 work, which inspired readings of medieval and rabbinic sources by Leo Strauss, Franz Rosenzweig, and Emmanuel Levinas. Cohen rejects the notion that we should try to understand texts of the past solely in the context of their own historical (...) era. Subverting the historical order, he interprets the ethical meanings of texts in the light of a future yet to be realized. He commits the entire Jewish tradition to a universal socialism prophetically inspired by ideals of humanity, peace, and universal justice. Through her own probing commentary on Cohen’s text, like the margin notes of a medieval treatise, Bruckstein performs the hermeneutical act that lies at the core of Cohen’s argument: she reads Jewish sources from a perspective that recognizes the interpretive act of commentary itself. (shrink)

Die vier Phasen der Philosophie und ihr augenblicklicher Stand nebst Abhandlungen über Plotinus, Thomas von Aquin, Kant, Schopenhauer und Auguste Comte. Unveränderter Print-on-Demand-Nachdruck der 2. Auflage von 1968. Inhalt: Einleitung I. Die vier Phasen der Philosophie (1895) II. Plotinus (1876) III. Thomas von Aquin (1908) IV. Über Kants Kritik der Gottesbeweise (1911/12) V. Schopenhauer 1911/12) VI. Auguste Comte (1869) VII. Über voraussetzungslose Forschung (1901) Anmerkungen Brentanos zu den vier Phasen der Philosophie Anmerkungen des Herausgebers zum Gesamtwerk Namen- und Sachregister.

Author continues the publication which appeared in the Acta Biotheoretica I, p. 113–132, regarding his results obtained in course of research work on superior plants:Picea excelsa trees, and furthermore on unicellular living beings, namely yeast cells . Author made a pure culture with the unicellular culture method, and by occasional inoculation produced successors therefrom. He established the progress in development by measuring, according to weight, the CO2 which arose in course of life. The ontogenetic course of development of the original (...) culture as well as that of the successors took the form ofS but theseS curves were not equally precipitous . When he drew theS-formed development curves in the measure of their time of inoculation in a rectangular co-ordinate system, he received a wave-surface . When he intersected the wave-surface with the abscissa and the plane parallel with the vertical axis, wave-like lines were the result, which resembled vibratory motion evolving around an axis producing a regular picture . Research has ascertained that the axis follows the laws of aperiodic vibratory motion, the undulating curve corresponds with the phenomenon of periodic vibratory motion, both of which are derived from the common differential equationd 2 s/dt 2 + 2r ds/dt +w 2 s=o. Any point of thes h axis following the aperiodic vibratory motion is given by the following equation: sh=a1e−r1t⋅e+tr21−w21√−e−tr21−w21√2⋅⋅⋅⋅⋅while the wave-curve showing thes h periodic movement is given by the following equation: sp=a2e−r2tcos⋅⋅⋅⋅⋅⋅⋅⋅The completey movement is made up of the total of the two vibratory movementsy=s h +s p . The research for the time being refers merely to the aperiodic axis. Calculations show that with thes h equation, the aperiodic axes belonging to all the sections can be followed exactly, as the time function oft, and moreover, the change according to time in the size of the w1, r1, a1 coefficients also shows definite regularity .Author deals separately with the calculation of the axis maximal time =t max and the maximal value = s h max of the wave-curve, and establishes that the development speed of every cell and every organism built up from cells has a maximal point of time and a maximal value. Thet maximum point of time: tmax=Ir12−w12−−−−−−−√logelogr+r12−w12−−−−−−−√r−r12−w12−−−−−−−√−−−−−−−−−−−√⋅⋅⋅⋅If we put thet max value in the place of the original equation of the axis we get the numeric value of thet max .Author finally establishes that the recognition of the fact that a harmonic vibratory motion plays a part in the evolution of living beings and that the axis of this complicated vibration follows the equation of aperiodic vibratory motion is a fundamental result in the theoretic study of the phenomena of life, which, besides, has also a great practical importance in the sphere of the study of improvement, inheritance and the biology of the species.L'auteur continue la publication des résultats de ses recherches faites sur des êtres vivants unicellulaires, notamment desSaccharomyces. Cette publication fut communiquée dans les Acta Biotheoretica I, p. 113–132. Par la méthode de la culture unicellulaire, l'auteur a créé une culture pure et, de celli-ci, au moyen d'inoculations périodiques, il a créé des descendants. Il a mesuré la marche du développement en pesant le CO2 produit au cours de la vie. La courbe d'évolution ontogénétique, tant de la culture-mère que des descendants, a présenté une ligne enS, mais chacun de cesS ne montait pas de la même façon . En représentant ces courbes d'évolution enS en fonction du temps et à l'échelle des périodes d'inoculation sur des coordonnées rectilignes, il obtenait une surface d'ondes . En coupant cette surface par un plan parallèle à l'abscisse et à l'axe vertical, il obtenait des lignes ondoyantes qui ressemblaient à un mouvement oscillatoire se formant autour d'un axe à l'image régulière . Les examens ont révélé que l'axe suit les lois du mouvement vibratoire harmonique apériodique et que la courbe ondoyante répond au phénomène du mouvement vibratoire harmonique périodique. L'un et l'autre provenant de l'équation différentielle communed 2 s/dt 2 + 2r ds/dt +w 2 s=o. N'importe quel point de l'axes h qui suit un mouvement vibratoire harmonique apériodique est déterminé par l'équation suivante: sh=a1e−r1t⋅e+tr21−w21√−e−tr21−w21√2⋅⋅⋅⋅⋅cependant que la courbe ondoyante s p qui montre un mouvement vibratoire harmonique périodique est exprimée par l'équation suivante sp=a2e−r2tcos⋅⋅⋅⋅⋅⋅⋅⋅Le mouvement complety se compose de la somme des deux mouvements oscillatoires,y =s h +s p .Pour le moment, les examens n'ont trait qu'à l'axe apériodique. Les calculs prouvent que par l'équation sh les axes apériodiques appartenant à toutes les coupes peuvent être suivis avec exactitude comme fonctions du tempst, et que même le changement de la valeur des coefficientsw 1 ,r 1 ,a 1, présente aussi une régularité nette .L'auteur examine ensuite le calcul du temps maximum=t max et, en outre, la valeur maximum =s hmax de l'axe de la courbe vibratoire et il énonce que toute cellule et tout organisme composé de cellules ont dans le cours de leur développement un temps maximum et une valeur maximum. Le tempst maximum sera: tmax=Ir12−w12−−−−−−−√logelogr+r12−w12−−−−−−−√r−r12−w12−−−−−−−√−−−−−−−−−−−√⋅⋅⋅⋅En substituant la valeur dut max dans l'équation originale de l'axe , on obtient la valeur numérique dut max .Finalement, après avoir déterminé le fait que dans le développement des êtres vivants, on est en présence d'un mouvement vibratoire harmonique périodique et que l'axe de cette oscillation complexe suit l'équation du mouvement vibratoire harmonique apériodique, l'auteur constate que cette détermination constitue un résultat fondamental pour l'étude théoritique des phénomènes vitaux et ce résultat possède en même temps une grande importance pratique pour l'étude de l'amélioration, du sélectionnement, de l'hérédité et de la biologie de la race. (shrink)

Nach den Teilen I (1973), II (1979), III (1988) und IV (1994) liegt hiermit der vorletzte Band des wohl umfangreichsten Übersetzungs- und Kommentieriungswerkes vor, das jemals einem byzantinischen Geschichtsschreiber gewidmet wurde. Leider war es aber dem unermüdlichen Bearbeiter nicht beschieden, sein großes Unternehmen noch mit dem sechsten Teil abzuschließen. Van Dieten ist am 26. 12. 2003 kurz vor seinem 80. Geburtstag gestorben.

This paper is the general introduction to a collection of essays entitled Franz Brentano and Austrian Philosophy (forthcoming). In this substantial introduction, I comment several aspects of the recent reception of Brentano’s philosophical programme in contemporary philosophy, and the actual debates on topics such as emotions, values, and intentionality, for example. It is divided in four parts corresponding to the four sections of the book. The first three sections contain 11 original contributions on Brentano’s philosophy and its place in (...) the history of philosophy in Austria, and the last section contains three unpublished manuscripts from Alfred Kastil et Moritz Schlick. I. Descriptive psychology and phenomenology: Brentano and Husserl II. Brentano and the Vienna Circle III. Brentano and the history of philosophy IV. Documentation: Alfred Kastil and the Vienna Circle . (shrink)

Husserl on the Ego and its Eidos (Cartesian Meditations, IV) ALFREDO FERRARIN THE THEORY OF the intentionality of consciousness is essential for Husserl's philosophy, and in particular for his mature theory of the ego. But it runs into serious difficulties when it has to account for consciousness's transcendental constitution of its own reflective experience and its relation to immanent time. This intricate knot, the inseparability of time and constitution, is most visibly displayed in Husserl's writings from the 192os up to (...) the notion of the eidos ego in the fourth Cartesian Meditation. In this paper I want to dwell on the most problematic aspects of this theory. After a few preliminary remarks about the intentionality of consciousness (sec- tion 1), I try to place the theory of the substrate of habitualities in the context of Husserl's evolution on the issue of the reflection of the ego on itself (section ~). I briefly follow the threads of Husserl's shifting position from the Logical Investi- gat/ons and Ideas I to Ideas II, the Cartesian Meditations and the Cr/s/s. I indicate Husserl's works are quoted with the following abbreviations: CM = Cartesiani.~he Meditationen, Husserliana Bd. I, hrsg. v. S. Strasser (Den Haag, 195o); Carte- s/an M~, trans. D. Cairns (Dordrecht, 196o ) SW = Husserl, Shorter Works, ed. P. McCormick and F. Elliston (Notre Dame, 198a) IZ = Zur Phttnomenologie des inneren Zeilheun~tseim (z 893-z 917), Husserliana Bd. X, hrsg. v. R. Boehm (Den Haag, 1966 ) Ideen I = ldeen zu einer reinen Ph~nomenologie und ph~nomenologischen Philosophic, Husserliana Bd. III, hrsg. v. W. Biemel (Den Haag, t95o); Ideas I, trans. F. Kersten (The Hague, Boston, Lancaster, s983) ldeen// = ld., Hussefliana Bd. IV, hrsg. v. M. Biemel (Den Haag, 1952); Ideas I1, trans. R. Rojcewicz and A. Schuwer (Dordrecht, Boston, London, x 989) FTL = Forma/e und transzendenta~ Log/k, Husserliana Bd. XVII, hrsg. v. P. Janssen (Den Haag, t974) Kr/sh = Kr/s/s der europ~/schen W/ssen~haften, Husserliana Bd. VI, hrsg. v. W. Biemel (Den Haag, 1954) I wish to express my gratitude to Pierre Kerszberg and Alessandra Fussi for their helpful com- ments on an earlier draft of the paper, and to Graham Harman for checking the final version of my English text. [645] 646 JOURNAL OF THE HISTORY OF PHILOSOPHY 32:4 OCTOBER 1994 some historical antecedents, in particular Aristotle, of Husserl's theory of abid- ing properties which, as far as I can see, have not been pointed out before. Husserl's Entwicklungsgeschichte on the topic of the pure ego has already been the object of important scholarly works, of which Kern's 1964 Husserl und Kant seems to me the best example. But what the secondary literature does not do is develop thematically the ambiguities of Husserl's definitions of consciousness and temporality in a unitary and comprehensive way. While I follow the lead of Berger, Broekman, Kern, Marbach,' and others, I find that their work does not sufficiently stress the difficulties at the core ofintentionality and reflective time- consciousness. Therefore, although section 2 is a necessary presupposition for drawing some critical conclusions in the final two sections, it does not exhaust my theme. After clarifying the peculiarity of the notions of essence, intuition, tran- scendental and apriori, as well as their irl:educibility to a Kantian meaning, I turn to the "de facto transcendental ego" resulting from eidetic variation (section 3) in order to introduce an examination of temporality. The difficul- ties in the twofold requirement, namely, that consciousness be the identical subject of its Erlebnisse and be synthetically unified in time, concern the unity, primacy, and mutual relation of time and consciousness in the constitution of our experience. They have been heady pointed out by Ricoeur in his commen- tary on the Cartesian Meditations. But what I want to argue in section 4, going beyond Ricoeur's text, is that the tension between temporally constituted and constitutive consciousness in the ego's reflection on its own retentions and protensions does not simply make the question of time ambiguous, but has crucial and problematic bearings on the very definition of consciousness as intentionality. In this respect... -/- . (shrink)

REF is the statement that every stationary subset of a cardinal reflects, unless it fails to do so for a trivial reason. The main theorem, presented in Sect. 0, is that under suitable assumptions it is consistent that REF and there is a κ which is κ+n -supercompact. The main concepts defined in Sect. 1 are PT, which is a certain statement about the existence of transversals, and the “bad” stationary set. It is shown that supercompactness (and even the failure (...) of PT) implies the existence of non-reflecting stationary sets. E.g., if REF then for manyλ ⌝ PT(λ, ℵ1). In Sect. 2 it is shown that Easton-support iteration of suitable Levy collapses yield a universe with REF if for every singular λ which is a limit of supercompacts the bad stationary set concentrates on the “right” cofinalities. In Sect. 3 the use of oracle c.c. (and oracle proper—see [Sh-b, Chap. IV] and [Sh 100, Sect. 4]) is adapted to replacing the diamond by the Laver diamond. Using this, a universe as needed in Sect. 2 is forced, where one starts, and ends, with a universe with a proper class of supercompacts. In Sect. 4 bad sets are handled in ZFC. For a regular λ {δ<+ : cfδ<λ} is good. It is proved in ZFC that ifλ=cfλ>ℵ1 then {α<+ : cfα<λ} is the union of λ sets on which there are squares. (shrink)

I present a formal theory of the logic and aboutness of imagination. Aboutness is understood as the relation between meaningful items and what they concern, as per Yablo and Fine’s works on the notion. Imagination is understood as per Chalmers’ positive conceivability: the intentional state of a subject who conceives that p by imagining a situation—a configuration of objects and properties—verifying p. So far aboutness theory has been developed mainly for linguistic representation, but it is natural to extend it to (...) intentional states. The proposed framework combines a modal semantics with a mereology of contents: imagination operators are understood as variably strict quantifiers over worlds with a content-preservation constraint. (shrink)

This paper explores Franz Brentano’s metaethics by comparing it to Thomas Reid’s. Brentano and Reid share a commitment to moral realism and they are both aptly classified as intuitionists concerning moral knowledge and the nature of moral judgment. However, their respective versions of intuitionism are importantly different, in ways that reflect more general differences between their respective epistemological views. Sections III and IV of the paper focus more exclusively on Brentano’s metaethics and some of its unorthodox features. These features (...) tie in with notorious difficulties for moral realism concerning the nature of moral truth and the relation between moral judgment and motivation to act. (shrink)

We need to understand the impossible. Francesco Berto and Mark Jago start by considering what the concepts of meaning, information, knowledge, belief, fiction, conditionality, and counterfactual supposition have in common. They are all concepts which divide the world up more finely than logic does. Logically equivalent sentences may carry different meanings and information and may differ in how they're believed. Fictions can be inconsistent yet meaningful. We can suppose impossible things without collapsing into total incoherence. Yet for the leading philosophical (...) theories of meaning, these phenomena are an unfathomable mystery. To understand these concepts, we need a metaphysical, logical, and conceptual grasp of situations that could not possibly exist: Impossible Worlds. This book discusses the metaphysics of impossible worlds and applies the concept to a range of central topics and open issues in logic, semantics, and philosophy. It considers problems in the logic of knowledge, the meaning of alternative logics, models of imagination and mental simulation, the theory of information, truth in fiction, the meaning of conditional statements, and reasoning about the impossible. In all these cases, impossible worlds have an essential role to play. (shrink)

Die in diesem Band vereinten Aufsätze spiegeln Brentanos späte Ansichten wieder; die Einleitung wurde für den allgemein philosophisch interessierten Leser konzipiert und behandelt Brentanos Theorie des Kontinuums, des Ursprungs des ...

"This book is the first of two volumes on belief and counterfactuals. It consists of six of a total of eleven chapters. The first volume is concerned primarily with questions in epistemology and is expository in parts. Among others, it provides an accessible introduction to belief revision and ranking theory. Ranking theory specifies how conditional beliefs should behave. It does not tell us why they should do so nor what they are. This book fills these two gaps. The consistency argument (...) tells us why conditional beliefs should obey the laws of ranking theory by showing them to be the means to attaining the end of holding true and informative beliefs. The conditional theory of conditional belief tells us what conditional beliefs are by specifying their nature in terms of non-conditional belief and counterfactuals. In addition, the book contains several novel arguments, accounts, and applications. These include an argument for the thesis that there are only hypothetical imperatives and no categorical imperatives; an account of the instrumentalist understanding of normativity, or rationality, according to which one ought to take the means to one's ends; as well as solutions to the problems of conceptual belief change, logical learning, and learning conditionals. A distinctive feature of the book is its unifying methodological approach: means-end philosophy. Means-end philosophy takes serious that philosophy is a normative discipline, and that philosophical problems are entangled with each other. It also explains the importance of logic to philosophy, without being a technical theory itself"--. (shrink)

Confucian scholars should satisfy two conditions insofar as they think their theories enable Confucianism to make contributions to liberal politics and social policy. The liberal accommodation condition stipulates that the theory in question should accommodate as many reasonable conceptions of the good and religious doctrines as possible while the intelligibility condition stipulates that the theory must have a recognizable Confucian character. By and large, Joseph Chan’s Confucian perfectionism is able to satisfy the above two conditions. However, contrary to Chan and (...) many other Confucian scholars, I argue that any active promotion of Confucianism will violate the liberal accommodation condition. I propose the “wide view of moderate perfectionism,” which enables Confucianism to shed light on a wide range of political and social issues without promoting Confucianism actively. Thus, I present a new approach to the long-standing question of how Confucianism may improve political and social development in a liberal society. (shrink)

Hermann Lotze was a key figure in the philosophy of the second half of the 19th century, influencing practically all leading philosophical schools of the late 19th and the early 20th century: (i) the neo-Kantians; (ii) Brentano and his school of descriptive psychology; (iii) the British idealists; (iv) Husserl’s phenomenology; (v) Dilthey’s philosophy of life; (vi) Frege’s new logic; (vii) the early Cambridge analytic philosophy; (viii) William James’s pragmatism. The book first presents the main ideas of Hermann Lotze’s philosophy (Part (...) I), and then traces his influence on the descriptive psychology of Franz Brentano and Carl Stumpf (Part 2) and Cambridge analytic philosophy (Part 3). In addition, the book includes Bertrand Russell’s conspectus of J. E. McTaggart’s 1898 lectures on Lotze. (shrink)

Growing out of concerns for environment-development interlinkages expressed at the United Nations Conference on the Human Environment, 1972, this volume is a compilation of edited versions of statements made at that conference and at the ...

As cause we often specify an event the occurrence of which first guaranteed that of the effect. This notion is explicated in a framework of branching worlds in Sections I to V. VI and VII point out its close relations to the concept of an agent's bringing about an event. The topic of the last two sections is the distinction between causes and necessary circumstances. For this purpose conditionals are used, interpreted with respect to branching worlds without a similarity relation (...) between them. (shrink)

This essay discusses the difficulty to reconcile two paradigms about beliefs: the binary or categorical paradigm of yes/no beliefs and the probabilistic paradigm of degrees of belief. The possibility for someone to hold both types of belief simultaneously is challenged by the lottery paradox, and more recently by a general impossibility theorem by Dietrich and List (2018, 2021). The nature, relevance, and implications of the tension are explained and assessed.

T × W logic is a combination of tense and modal logic for worlds or histories with the same time order. It is the basis for logics of causation, agency and conditionals, and therefore an important tool for philosophical logic. Semantically it has been defined, among others, by R. H. Thomason. Using an operator expressing truth in all worlds, first discussed by C. M. Di Maio and A. Zanardo, an axiomatization is given and its completeness proved via D. Gabbay’s irreflexivity (...) lemma. Given this lemma the proof is more or less straight forward. At the end an alternative axiomatization is sketched in which Di Maio’s and Zanardo’s operator is replaced by a version of “actually”. (shrink)

This book’s goal is to give an intellectual context for the following manuscript. -/- Includes bibliographical references and an index. Pages 1-123. 1). Philosophy. 2). Metaphysics. 3). Philosophy, German. 4). Philosophy, German -- 18th century. 5). Philosophy, German and Greek Influences Metaphysics. I. Hegel, Georg Wilhelm Friedrich -- 1770-1831 -- Das älteste Systemprogramm des deutschen Idealismus. II. Rosenzweig, Franz, -- 1886-1929. III. Schelling, Friedrich Wilhelm Joseph von, -- 1775-1854. IV. Hölderlin, Friedrich, -- 1770-1843. V. Ferrer, Daniel Fidel, 1952-. [Translation (...) from German into English of the-- Das älteste Systemprogramm des deutschen Idealismus.]. -/- Note: the manuscript is in the handwriting of G.W.F. Hegel, but the actual authorship is disputed. No date is given. Franz Rosenzweig made up the title as it is known today. He published the text in 1917. At that time, F. Rosenzweig thought F.W.J. Schelling was the author. No one has read this book for errors. As always, any errors, mistakes or oversights etc. are mine alone. Given a couple more years, I could improve this book. This is a philosophical translation and not a philological translation. Martin Luther who did the famous early translation of the Bible into German wrote in a letter, “If anyone does not like my translation, they can ignore it… (September 15, 1530)”. There are no ‘correct’ translations. Some are just better than other translations. -/- The Oldest Systematic Program of German Idealism. The German title is: Das Älteste Systemprogramm Des Deutschen Idealismus. This title was made up by Franz Rosenzweig in 1917, when he first published the manuscript. He found the manuscript in the Royal Library in Berlin in 1913. The manuscript suggested date is around 1796 and was done by handwriting research. However, the manuscript is not dated. The Prussian State Library auctioned in March 1913 from the auction of the house Liepmannssohn in Berlin a single sheet on the front and back with Hegel's cursive handwriting. The manuscript was lost during WWII. But Dieter Henrich found it again in 1979 in the “Biblioteka Jagiellonska” in Krakow (Poland), where it is today. Address: Jagiellonian Library, Jagiellonian University, al. Mickiewicza 22, 30-059 Cracow, Poland. Later research suggests that manuscript had come from the estate of Hegel’s student Friedrich Christoph Förster (1791-1868). He was one of the editors of Hegel’s posthumous works and most likely had access to a number of Hegel’s manuscripts. This text actually being one of them. Hegel traveled around Bohemia with Marie and Friedrich Christoph Förster around the year 1820-21 (see Klaus Vieweg). -/- Philosophical mystery -- who is the author or authors of this text? -/- Take a plunge into the deep and cold waters. Maybe a quagmire or quandary, but decidedly interesting. This project is to contextualize an old handwritten manuscript which is about 225 years old. The actual author is a mystery. I offer my own assessment. You can make your own assessments. The mystery has continued to unfold since 1917. There is plenty to read. Otherwise, think about the authorship and read more of the German philosophers and authors from this period and enjoy the depth of thinking and philosophizing. On one hand, there is just the sheer fun in the puzzle of the authorship questions; and on the other hand, these are the alluring thoughts that lead to the nascent stage of German Idealism and our intellectual heritage. There is no end to the accolades for this group of philosophers. A heritage that we still hear in in our attempts to move forward into our future. -/- Do your own astute exegesis (ἐξήγησις) as all paths are still open. Let your thought take to the wings of what is called thinking with this text. Critical encounters (Auseinandersetzung, or a Gegenüberstellung) with at least: Friedrich Hölderlin (1770-1843) Friedrich Wilhelm Joseph Schelling (1775-1854), and Georg Wilhelm Friedrich Hegel (1770-1831) --- starts here! German Idealism. We are not going to study this situation endlessly, instead we make some broad strokes and provide you a general context. You are allowed to read between the lines too. Goal: to understand the overall affinity and differences between the intellectuals of this period in German history; and to come to grips with this demanding text within its large scholarly context in the last 100 years. There are no final answers. (shrink)

The importance of the economic valuation of nature is frequently emphasised in the argument that more and better economic valuation will prevent the undervaluation and thereby the degradation of nature. The proponents of this ‘economic’ approach assume that rationality, human interaction and the nature of the good remain unchanged. However, the relationship between humans and nature necessarily undergoes change, and the biological and neurophysiological aspects of human nature must be considered to ensure the well-being and survival of humankind. In this (...) paper, I discuss the shortcomings of economic valuation with reference to the above objections, and present scenarios that illustrate the changing relationships between socio-ecological interconnectedness and the integrative capacity of institutions. (shrink)

This essay explores Aristotle’s conception of the active intellect or nous poiētikos. The earliest, medieval, and most recent interpretations of this concept are discussed. It is argued that even Aristotle’s immediate disciples disagreed in their conception of the active intellect, nor was there any more unanimity in the Middle Ages. According to Trendelenburg, the difficulty of the Aristotelian doctrine lies in the fact that the nous is sometimes said to be so intimately connected with the other faculties of the soul (...) that it appears to be incapable of existing without them. When it is viewed the highest nous, as nous poiētikos, it is separated from the rest of human nature and contrasted with it as something higher and its ruler. (shrink)