Theory and History of Ontology

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Franz Brentano's Ontology and His Immanent Realism


"Brentano was a philosopher and psychologist who taught at the Universities of Würzburg and Vienna. He made significant contributions to almost every branch of philosophy, notably psychology and philosophy of mind, ontology, ethics and the philosophy of language. He also published several books on the history of philosophy, especially Aristotle, and contented that philosophy proceeds in cycles of advance and decline. He is best known for reintroducing the scholastic concept of intentionality into philosophy and proclaiming it as the characteristic mark of the mental. His teachings, especially those on what he called descriptive psychology, influenced the phenomenological movement in the twentieth century, but because of his concern for precise statement and his sensitivity to the dangers of the undisciplined use of philosophical language, his work also bears affinities to analytic philosophy."

From: Roderick M. Chisholm and Peter Simons, " Brentano, Franz Clemens" in: Routledge Encyclopedia of Philosophy, Edited by Edward Craig, London: Routledge 1998.

"Brentano never presented his philosophy in completed form. Most of his doctrines are known to us from writings published after his death, and these do not contain any rounded out statement of his views. Brentano was not among those who in a moment of intuition sketch the architectonics of a system, leaving the relevant details to be fitted into it later. His research, always problem-oriented, began with individual questions, then went on to seek an absolutely certain, or if this could not be obtained, at least a probable, solution for the difficulties encountered along the way. Nor did he hesitate to revise his previous conceptions on the basis of advances in knowledge. The 'will to truth' checked the growth of a 'will to construct', and prevented the congealing of earlier ideas.

Brentano's significance for contemporary philosophy is still singularly underestimated. There is a striking disparity between the very great effect he has had on present-day philosophy and the relatively meager attention paid his teachings in current philosophical instruction and research. For Brentano is a center from which threads extend in the most varied directions. In the first place, the entire philosophy of phenomenology would be inconceivable without him. He was the teacher of Husserl (on whom he had an influence that should not be underestimated) and was thus the spiritual grandfather, so to speak, of Max Scheler and Martin Heidegger. Secondly, his work in ontology and metaphysics, notably his analysis of categories and his penetrating studies of Aristotle, decisively influenced the contemporary philosophies of Being (even if very indirectly in part). Finally, his method - especially in the study of the logic of language, which he considers the starting-point in philosophy bears a remarkable resemblance in many respects to the procedure of present day empiricism, and particularly to that of analytic philosophy in Britain and the U.S.A. It is difficult to say how much the investigations conducted in these countries owe to his stimulating ideas."

From: Wolfgang Stegmüller, Main Currents in Contemporary German, British, and American Philosophy, Dordrecht: Reidel Publishing Co., 1969, p. 24.

"Franz Brentano did not like to publish books; as he once said, he hated the "secondary work" that was connected with proof-reading, referencing of quotations, etc. He thus left the publication of his literary remains to his disciples. Indeed, after his death (1917) Alfred Kastil and Oskar Kraus undertook the publication of his literary remains and, in the time permitted to them, carried it out with great loyalty and dedication. In the years 1922 through 1934, there appeared in Felix Meiner's Philosophische Bibliothek ten volumes of Brentano's works; the editor's rich annotations are invaluable for understanding Brentano's lectures and the development of his thoughts. After Kastil's death the work of publication was taken over by Franziska Meyer-Hillebrand, his disciple." (p. 94)

From: Hugo Bergmann, "Brentano on the History of Greek Philosophy", Philosophy and Phenomenological Research 27, 1967, pp. 94-99.


"Brentano's first concern in psychology was to find a characteristic which separates psychological from non-psychological or 'physical' phenomena. It was in connection with this attempt that he first developed his celebrated doctrine of intentionality as the decisive constituent of psychological phenomena. The sentence in which he introduces the term 'intentionality' is of such crucial importance that I shall render it here in literal translation: Every psychical phenomenon is characterized by what the Scholastics of the Middle Ages called the intentional (or sometimes the mental) inexistence of an object, and what we should like to call, although not quite unambiguously, the reference ( Beziehung) to a content, the directedness ( Richtung) toward an object (which in this context is not to be understood as something real) or the immanent-object quality ( immanente Gegenständlichkeit). Each contains something as its object, though not each in the same manner. In the representation ( Vorstellung) something is represented, in the judgment something is acknowledged or rejected, in desiring it is desired, etc. This intentional inexistence is peculiar alone to psychical phenomena. No physical phenomenon shows anything like it. And thus we can define psychical phenomena by saying that they are such phenomena as contain objects in themselves by way of intention (intentional). (1)Actually, this first characterization of the psychological phenomenon makes use of two phrases: 'intentional inexistence' and 'reference to a content.' It is the first of these phrases which has attracted most attention, and it has even given rise to the view, supported by both anti-scholastics and neo-scholastic critics, that this whole doctrine was nothing but a loan from medieval philosophy. While a quick reading of the passage may seem to confirm this view, it is nevertheless misleading. 'Intentional inexistence,' which literally implies the existence of an 'intentio' inside the intending being, as if imbedded in it, is indeed a Thomistic conception. But it is precisely this conception which Brentano himself did not share, or which in any case he abandoned, to the extent of finally even dropping the very term 'intentionality.' Thus, the second characterization of the psychic phenomenon, 'reference to an object,' is the more important and the only permanent one for Brentano; it is also the one listed exclusively in the Table of Contents, beginning with the first edition. What is more: as far as I can make out, this characterization is completely original with Brentano, except for whatever credit he himself generously extends to Aristotle for its 'first germs' in a rather minor passage of the Metaphysics (1021 a 29). It was certainly none of Brentano's doing that this new wholly unscholastic conception came to sail under the old flag of 'intentionality.' Reference to an object is thus the decisive and indispensable feature of anything that we consider psychical: No hearing without something heard, no believing without something believed, no hoping without something hoped, no striving without something striven for, no joy without something we feel joyous about, etc. Physical phenomena are characterized, by contrast, as lacking such references. It also becomes clear at this point that Brentano's psychological phenomena are always acts, taking this term in a very broad sense which comprises experiences of undergoing as well as of doing, states of consciousness as well as merely transitory processes. Here, then, Brentano for the first time uncovered a structure which was to become one of the basic patterns for all phenomenological analysis."

(1) Psychologie vom empirischen Standpunkt I, Buch II, Kapitel I 5 (pp. 125 f.; English translation p. 88).

From: Herbert Spiegelberg, The Phenomenological Movement. A Historical Introduction, The Hague: Martinus Nijhoff, 1963 (Third Edition). pp. 36-37.

"Of great importance is Brentano's classification of psychic phenomena. There are three classes: presentations, judgments, and emotive acts. Of the first Brentano claims that all psychic phenomena are either presentations or involve presentations (a statement accepted by Husserl in an interpretation of presentations as "objectivating acts"). Judgments are conceived by Brentano as acts of affirmation or negation; thus he rejects a propositional theory of judgment. The third class ( Akte der Gemütsbewegung) contains acts of volition as well as emotions, feelings, etc. These acts are conceived in analogy to judgments; they are either positive or negative (love vs. hate) and they are correct or incorrect (love is correct if its object is intrinsically worthy of being loved). This led Brentano to a conception of ETHICS as a discipline parallel to LOGIC. His basic ideas in ethics were first published as a paper he delivered in Vienna in 1889 ( Vom Ursprung sittlicher Erkenntnis; an English translation, Our Knowledge of Right and Wrong, already appeared in 1902). His ethics had a strong influence on Max Scheler and on G. E. Moore (1873-1958). In his later writings Brentano became more and more interested in developing his own ontology and theory of categories. He developed a position called "reism" according to which the basic category is that of res, which comprehends both concrete things and immaterial souls. This strict objectivistic attitude was initially not influential within the phenomenological movement, but it did become important for logic and ontology in Poland. In recent years these ideas have had great influence on philosophers such as Roderick Chisholm and Barry Smith.

Of great influence on Husserl was Brentano's theory of wholes and parts, which he introduced in his "ontology," the second part of his Würzburg lectures (in the 1870s Brentano inserted a descriptive part that he called "phenomenology" between the abovementioned "transcendental philosophy" and the "ontology"). Ontology has as its basic distinction that between collectiva and divisiva, which dichotomy is in turn classified as physical, logical, and metaphysical. The influence on Husserl's formal and material ontology as developed in the third of his Logische Untersuchungen (1900-1901) is obvious, and it is likely that Husserl knew about these lectures via Stumpf, to whom he refers in this context and who had an extensive copy of these lectures.

The concept of Intentionality is only a problematic link between Brentano and phenomenology. This is already indicated by the fact that Brentano later gave up the term "intentional" because he thought that his views in this connection had been misunderstood. As a matter of fact Brentano does not talk about intention or intentionality, but rather uses expressions like "intentional inexistence" or "intentionally contain" that he introduced in order to distinguish psychic phenomena from physical phenomena. An isolated quality such as red is a physical phenomenon; red as belonging to consciousness is on the other hand a psychic phenomenon.

Intentional inexistence can be regarded as a mereological concept on two different levels. On the descriptive level, a psychic phenomenon is part of a complex consciousness to which belong, for instance, inner perception, acts of judgment, and emotive acts; on the metaphysical level, which also embraces entities that are not immediately given but inferred, it is conceived as part of a soul. In contexts like "intentional inexistence," the term "intentional" does not determine the related expression "inexistence" (or "containment") but modifies it, i.e., it changes its original meaning. If these words were used in this original meaning, the following conclusions would be valid: if something exists in something else, then both things exist; if something is contained in something other than it, there is a spatial relation between them. In the modified context of "intentional inexistence" and "intentional containment," however, both conclusions are invalid. The intentional relation is thus, as Brentano explains in later writings, only "something relation-like" ( etwas Relativliches). It is not, as in Husserl's intentional acts, a matter of directedness toward an object transcendent to consciousness but, in contrast, something immanent to consciousness."

From: Dieter Münch, "Franz Brentano" in: Lester Embree et alii (eds.), Encyclopedia of Phenomenology - Dordrecht: Kluwer, 1997, pp. 74-75.


"The standards of rigour and descriptive adequacy of Scholasticism were re-established above all by Franz Brentano and his school. Brentano, a pupil of Adolf Trendelenburg, one of the few Aristotelians in the 19th century in Germany, created a philosophical system which was a synthesis of Aristotelianism, Cartesianism, and the empiricism of The British School. This system was modified in different and often highly original ways by his pupils, the most important of whom were Kazimierz Twardowski, Edmund Husserl, Carl Stumpf, Christian von Ehrenfels, Anton Marty, and Alexius Meinong.

In contradistinction to Hegel and his fellow idealists, the Brentano School was very successful in associating its philosophical work in fruitful ways with modern developments in the sciences, above all in psychology and linguistics. Brentano’s pupils were responsible for founding not only new philosophical movements such as phenomenology, but also new programmes of scientific research such as the Gestalt theories of the Graz and Berlin Schools. Brentano’s pupils contributed in important ways to modern logic, above all through Twardowski and his students in Poland. And they contributed also to ontology, for example through Meinong and the members of The Graz School, who established the so-called theory of objects. Husserl, following in some respects in Meinong’s footsteps, founded in turn the discipline of formal ontology and was the first to analyse in formal manner the ontological concepts of dependence, part and whole. Husserl’s work in this field was then continued in philosophy above all by Adolf Reinach and Roman Ingarden, and in its application to linguistic parts and wholes by Stanislaw Lesniewski and others in Poland. Husserl’s philosophical ideas on formal and material ontology gave rise further to a new understanding of synthetic or material a priori truths. From the perspective of Husserl, Reinach, and Ingarden such truths are not, as for Kant, the products of a forming or shaping activity on the side of the subject. Rather, as for Aristotle, they represent intelligible strictures on the side of the objects of experience, structures which are not invented but discovered, and which serve, again, as a pre-empirical basis for science and philosophy."

From: Introduction to: Handbook of Metaphysics and Ontology, Edited by Barry Smith Barry and Hans Burkhardt, Munich: Philosophia Verlag 1991, pp. XXI-XXII.


On the website "Theory and History of Ontology"

Editions, Translations, Bibliographical Resources

Selected Bibliography on the Philosophical Work of Franz Brentano:

First part: A - K

Second Part: L - Z