[Open Access] Alexis Delamare, The Power of Husserl’s Third Logical Investigation. Formal and applied mereology in Zur Lehre von den Ganzen und Teilen. In: Studia Phaenomenologica, Volume 21/ 2021

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The Power of Husserl’s Third Logical Investigation: Formal and Applied Mereology in Zur Lehre von den Ganzen und Teilen

Alexis Delamare
Université de Rouen / ERIAC, Universität Heidelberg

Abstract: The peculiar legacy of Husserl’s mereology, chiefly studied by analytic philosophers interested in ontology, has led to a partial understanding of this Investigation, which is too often reduced to a chapter of “formal ontology”. Yet, the power of the III. LU goes far beyond: it enabled Husserl to deal, in the framework of a unified theory, with a vast range of particular problems. The paper focuses on one of these issues, namely abstraction, so as to expose how Husserl instrumentalizes his formal tools in order to tackle material issues. The existence of an up and down pattern is uncovered: Husserl first reinterprets the psychological problem of abstraction in ontological terms (“bottom-up”), before coming back to the original problem with new insights (“top-down”). The second, correlative aim of the paper is to emphasize the key role played by Friedrich Schumann, a forgotten yet crucial character for Husserl’s conception of abstraction.
Keywords: Husserl; Logical Investigations; Mereology; Abstraction; Formal Ontology.

Introduction. The legacy of the Third Investigation

The Third Investigation, entitled “On the theory of wholes and parts” (“Zur Lehre von den Ganzen und Teilen”), seems to occupy a very specific place in the organization of Husserl’s Logische Untersuchungen (Smith, D.W. 2003a: 25), universally acknowledged as the birth record of phenomenology. Indeed, as Husserl himself recognizes, the III. LU, because of its “ontological themes”, cannot be regarded as “purely phenomenological” (VI. LU: 236 [II: 343]).
This particularity accounts for the originality of its legacy. While issues pertaining to parts and wholes seem to have entirely vanished in the phenomenological tradition , they have been abundantly tackled by analytic philosophers . In this framework, the Third Investigation is widely recognized as a pioneer work in mereology, which anticipates the first mathematical accounts given in Leśniewski (1927) and Leonard and Goodman (1940). This situation has led to a specific interpretation of this Investigation, since its readers were chiefly interested in the ontological significance of Husserl’s concepts. Accordingly, they accurately emphasized the inclusion of mereology within formal ontology (Crosson 1962; Simons 1982: 115; Poli 1993; Albertazzi 1996; Smith, B. 2000, 297–298; Smith, D. W. 2003b; Varzi 2019). Yet, such reading may be too restrictive if it does not stress, at the same time, the decisiveness of Husserl’s theory of wholes and parts for a great variety of regional or material issues.
The aim of this paper is thus twofold.
First, I want to emphasize the broad spectrum of issues tackled by Husserl in the III. LU. Mereology is, so to speak, a Swiss knife for Husserl: a single tool addressing a wide range of topics. We can even go so far as to say, with Sussbauer (1995: 30) and Drummond (2008: 120), that the III. LU is a requirement for the understanding of the whole Husserlian project . Explicit or implicit references to its analyses indeed pervade his materials throughout his career: they are to be found in texts engaging with pure grammar (especially in the IV. LU) , ethics (Husserl 1988: 77, 322), theory of judgment (Husserl 2000, XXXI: 48, 95), and, of course, phenomenology, as the V. LU suffices to show (Sokolowski 1968) . In this paper, I will focus on one particular application, namely abstraction. Even though this theme has received attention in the literature (Rollinger 1993), its role is too often reduced as the historical origin of Husserl’s formal-ontological concepts . As a result, the fact that Husserl suggested positive, material solutions to this issue thanks to his mereological tools is almost always overlooked .
The second aim of the paper is to expose the up and down movement that is here noticeable. The situation is actually similar to what occurred in the history of algebra: it was only thanks to the introduction of formal tools (later called group theory) that Galois was able to tackle the specific problem of the solvability by radicals of equations of degree 5 and more. Husserl adopts the same perspective. It is an up and down pattern—first, formalization, then material application—that accounts for the power of this Third Investigation, that is, the capacity of mereological concepts to sustain original viewpoints on one of the most heated debates that animated the philosophical circles at the turn of the 20th century.
Accordingly, the paper is structured in two parts. I first reconsider the inclusion of the Third Logical Investigation within formal ontology and thus its intrinsic value as an important piece of knowledge in itself. My aim is in particular to determine the status of mereology among other formal-ontological disciplines—a task that has not been undertaken yet in Husserlian scholarship. In the second part, I show how these formal tools obtain a new, instrumental value as they help Husserl to address the aforementioned issue of abstraction. On this topic, emphasis will be placed on the polemical dimensions of Husserl’s positions, and more particularly on the debate with Friedrich Schumann, a forgotten yet crucial character to fully understand Husserl’s position. In the conclusion, I will briefly show to what extent the very same up and down movement is also manifest regarding Husserl’s doctrine on Gestalt qualities.

  1. Mereology and formal ontology

1.1. The historical context of the Third Investigation central concepts: Selbständigkeit and Fundierung

Husserl’s mereology cannot be understood apart from its historical context. The latter is in fact threefold: Husserl rearranges issues and concepts developed by Brentano, by Stumpf, and by Meinong.
Let’s start by recalling the definition of a part proposed by Husserl:

We may call anything a part that can be distinguished “in” an object, or, objectively phrased, that is “present” in it. A part is everything that an object “has” in a “real” (or, better, “reel”—reellen) sense, in the sense of something actually making it up. (III. LU: 228 [II: 5, trans. modified])

As Husserl himself emphasizes, “the term part is not used so widely in ordinary discourse” (III. LU: 228 [II: 5]). According to Husserl’s concept, the red moment and the spherical form of a red ball must indeed be regarded as parts of the latter, while it is not the case in everyday language, which considers only pieces—like a piece of cake or a player in a team—to be actual parts of objects. Husserl’s extension of the concept of part was influenced by Brentano and Stumpf.
Brentano was the first to pave the way for this generalized notion of part . In his Würzburger metaphysics lectures of 1867, he distinguished between the physical and the metaphysical parts of an object, the latter being in fact the determinations of the thing, such as its height or its color, that cannot be separated from the thing itself (Baumgartner and Simons 1994: 61). Husserl learnt about this distinction via Stumpf who had copies of these lectures (Münch 1997: 74), and pervasively appeals to it in his early writings , especially in his Habilitationschrift (Husserl 1970: 292, 293, 324, 300, 330–334), in the Philosophy of Arithmetic (thereafter, PA) (Husserl 1970: 19, 56, 68, 71, 72, 82, 100, 152, 159, 195), and in his crucial Psychologische Studien zur elementaren Logik (Husserl 1979: 96–97). Yet, in the III. LU, it is Carl Stumpf, to whom the Investigations are dedicated, that is explicitly mentioned as Husserl’s main source of inspiration.
As Husserl acknowledges (III. LU: 225 [II: 3]), it is indeed Stumpf that forged the notion of selbständige (“independent”) contents in his Über den psychologischen Ursprung der Raumvorstellung (Stumpf 1873: 109) . Dealing with the perception of space, Stumpf emphasizes that color and extension cannot exist independently from each other, that they are, in his terminology, only “Theilinhalte” (“partial contents”) and not “selbständige Inhalte” (“independent contents”) (Stumpf 1873: 109).
It is this Stumpfian background that enabled Husserl to build his extended notion of part, first in 1894 (Husserl 1979: 92–100), and then in the Third Investigation. Here, the couple of extension and color becomes the paradigm of “non-independent” (unselbständige) parts, or what Husserl also calls “abstract parts” or “moments” , as opposed to those parts (called independent [selbständige] parts or pieces [Stücke]) that can exist on their own. Following Stumpf (1873: 111; see Kaiser El-Safti 1994: 108), Husserl emphasizes that the inseparability of two non-independent contents does not rest on a subjective association and is thus to be understood, in Husserlian terms, as a (synthetic) a priori law, which draws solely on the ideal Species to which the particular objects belong (e. g., Color or Extension). These laws of dependence are ensured by appealing to a self-evident ideation which grasps their ideal necessity:

Non-independent objects are objects belonging to such pure Species as are governed by a law of essence to the effect that they only exist (if at all) as parts of more inclusive wholes of a certain appropriate Species. (III. LU: 240 [II: 12])

However, this explicit Stumpfian background is not sufficient to fully understand the concepts used by in the III. LU. It must indeed be noted that the essential notion of fundierte Inhalte (founded contents) is not employed by Stumpf. The latter actually originates in Meinong’s 1891 essay Zur Psychologie der Komplexionen und Relationen (Meinong 1891), where Meinong engages with von Ehrenfels’ seminal paper Über Gestaltqualitäten (von Ehrenfels 1890). Von Ehrenfels employed the term Grundlage (von Ehrenfels 1890: 236) to depict the sensible elements at the base of the Gestalt (such as the notes of a melody). Meinong modified von Ehrenfels’ terminology and decided to call this Grundlage “founding content” and the Gestalt itself “founded content”, the former being “selbständig”, while the latter is regarded as “unselbständig” (Meinong 1891: 253). As early as 1894, Husserl mentions Meinong’s essay and concept (Husserl 1979: 95). However, in these Psychologische Studien, Husserl focuses on Stumpf’s distinction between selbständige contents and Theilinhalte while the one between “founded” and “founding” contents does not play a key role—the concept of Fundierung as such is not even mentioned. It is thus only in 1900–1901, after the publication of Meinong’s Beiträge zur Theorie der psychischen Analyse in which the term Fundierung emerges (Meinong 1894: 380), that Husserl fully grasps the significance of this concept for his part/whole theory.
Here is Husserl’s definition of foundation in the LU:

If a law of essence means that an A cannot as such exist except in a more comprehensive unity which associates it with an M, we say that an A as such requires foundation by an M or also that an A as such needs to be supplemented by an M. (III. LU: 261 [II: 25])

Importantly, such foundation may be reciprocal or one-sided . The paradigmatic couple of color and extension exemplifies reciprocal foundation, while the foundation of a judgment or an affective act upon its underlying Vorstellung is a case of one-sided foundation .
The introduction of this Meinongian concept of Fundierung finally allows Husserl to reformulate the concept of independence: an object A will be said non-independent if it requires a foundation, and independent otherwise.

1.2. Husserl’s formalization of the concept of part

As a result of this historical inquiry, it appears that Husserl’s main definitions and theses about (in)dependence and foundation, on which the entire Investigation is based (e.g. the definition of a whole (III. LU: 275–276 [II: 34])) essentially come from a rearrangement of Brentanian, Stumpfian, and Meinongian insights. Husserl’s originality thus does not lie in the invention of the concepts at stake but, rather, on the conversion of meaning he achieves. We saw that Brentano and Stumpf already generalized the usual concept of part: they have expanded its extension, since the color of the chair or the intensity of a sound are now considered a part of these objects. Yet Husserl’s operation is not a mere generalization, but must be seen, rather, as an authentic formalization. The §13 of the Ideen I emphasizes the crucial difference between Generalisierung and Formalisierung (Husserl 1982: 26). To generalize (a law, a statement, or a concept) means to successfully apply it to an extended sphere of objects. Mathematical examples are illustrative. For instance, the passage from definite integral to improper integral is a generalization of the latter concept to infinite intervals (Cauchy 1823: 93–94). The initial concept is successfully applied to new objects: its extension is wider than originally.
The operation of formalization is entirely different. A law or a concept is formalized if it is applied, not to a greater sphere of objects, but to objects in general, to mere “somethings”. In other terms, a concept is formalized if it is transformed into a formal-ontological category. Formal ontology is indeed defined by Husserl as the science that deals with objects qua objects, with objects as such (Prolegomena: 244 [I: 153]; Husserl 1982: 20–23). This science only appeals to basic concepts whose extension is universal and not restricted to a particular region of being. The concepts of “Object”, “Unity”, “Number”, or “Relation” are usual examples of formal categories (Prolegomena: 244 [I: 153]). The purpose of formal ontology is to determine, thanks to a small number of “axioms” (III. LU: 252 [II: 19]), the relationships between these formal concepts, and, in so doing, to depict the analytic a priori laws between objects as such.
It is now clear why Husserl’s renewal of the mereological concepts is not a mere generalization. Husserl does not only subsume new instances under these notions, as Brentano and Stumpf did; on the contrary, he radically transforms their ontological significance. Part, whole, dependence, foundation, are not concepts that are restrained to a specific sphere of objects. It must be recalled at this point that this idea was far from being self-evident in the Brentanian school. Höfler (1890: 22), Meinong (1889: 202), and Twardowski (1894: 51) all asserted that mereological concepts were limited to contents of presentation. On the contrary, as soon as his 1894 initial essay, Husserl emphasizes that the concepts of parts and wholes do not primarily apply to Vorstellungen but to objects (Husserl 1979: 99) , and are thus not limited to the material sphere of psychical acts. This is why, in the III. LU, mereological concepts are included in the list of formal categories: “Something, One, Object, Quality, Relation, Association, Plurality, Number, Order, Ordinal Number, Whole, Part, Magnitude” (III. LU: 252 [II: 19]).

1.3. The intrinsic value of mereology

This inclusion of mereology within formal ontology immediately calls for a question. It seems plain that some formal categories are posterior to others: for instance, number is derived from plurality. This leads to the idea of a hierarchy between those concepts. Since Husserl agrees with Bolzano that the exposition of a theory must rest on the objective, systematic connections between the things themselves (Prolegomena: 15, 231–232 [I: 18, 144–145]), we are right in asking which are the highest formal categories, and which are the derived ones. Such requirement applies to mereological concepts. What is their position within formal ontology? Is mereology one of the first chapters, or only a remote, secondary section? As far as I know, this issue, despite its significance, has not been addressed in the literature.
I would like to show that mereology has actually a fundamental status. Such hypothesis finds its justification in the 1906/07 Logic lectures, where Husserl asserts that there is “a natural ordering of theories and disciplines” within pure logic (Husserl 1984b: 68–69; Husserl 2008: 66). In these lectures, Husserl appeals to a criterium of universality so as to uncover such ordering. Even though his only explicit use pertains to the priority of apophantic disciplines (governing the sphere of propositions) over ontological ones (Husserl 1984b: 69; Husserl 2008: 67), it is actually possible to apply the very same criterion directly to ontological disciplines. In this perspective, the concepts of quantity and number appear to rest on the concept of whole, the former being based on “wholes of the same type”, and the latter on wholes which are “divisible into equal parts” (Husserl 1984b: 77–78; Husserl 2008: 75) . The universality criterium thus leads to a hierarchy of the corresponding disciplines: mereology encompasses theory of quantity, which in turn includes arithmetic. In addition, the theory of series, and thus ordinal theory, is also depicted by Husserl as an application of mereology (Husserl 1984b: 77; Husserl 2008: 75).
It thus appears that most areas of mathematics (geometry excepted) are based on mereology. This relationship reveals the significance of mereology within the field of formal ontology: it is undoubtedly one of its most prominent sub-theories. In this perspective—let’s recall that formal ontology is one of the most important branches of knowledge (Prolegomena: 223–224 [I: 141])—mereology appears to possess an intrinsic scientific value.

1.4. The illustrative value of mereology

Besides, mereology also contributes to exemplify what formal ontology is. As the Prolegomena acknowledge, pure logic may seem to be “an insignificant field of more or less trivial statements” (Prolegomena: 223-224 [I: 141]). In order to remove this “prejudice”, it is necessary to undertake “particular concrete developments, which will provide a more precise idea of the content and character of the essential logical researches” (Prolegomena: 223 [I: 141; trans. modified]). The III. LU plays a key role to address this task, since the theory of parts and wholes appears to be the most advanced of those special investigations in 1900–1901. As a result, mereology also displays an illustrative value, since it is, so to speak, the cutting edge of pure logic in the LU.
This illustrative value is particularly manifest regarding the methodology of formal ontology. The latter methodology rests upon the intuitive presentation of the concepts involved. As Husserl explains in the Prolegomena, we must accomplish an “insight into the essence” (Prolegomena: 244 [I: 154]) of those concepts in order to escape ambiguity and confusion, and to depict the a priori laws that govern them. Such methodology, famously recalled in the Introduction to the second volume—“we must go back to the ‘things themselves’” (6 [I: 168])—is precisely the procedure used in the III. LU. For example, the necessity for dependent parts to be supplemented by other contents “comes, by its very nature, to donation in consciousness of apodictic self-evidence” (III. LU: 239 [II: 12, trans. mod.]).

  1. The application of mereological categories to the problem of abstraction

2.1. Introductory precisions

Yet Husserl’s concepts of part and whole do not owe their worth only to their intrinsic and illustrative value. A third dimension is indeed at stake, that I would call the instrumental or applied value of mereology. In what follows, I will focus on its application pertaining to the issue of abstraction.
The problem of abstraction was a notable theme of research in Brentano’s school, especially after Meinong’s publication of his Hume-studien (Meinong 1877; Meinong 1882). In the Second Investigation, Husserl proposes a series of historical and critical comments mostly directed against nominalism. My aim is to show that Husserl’s criticisms are fundamentally rooted in the formal-ontological concepts he developed in the III. LU, and that it is only in light of such concepts that his objections receive their full meaning.
To establish this point, I will concentrate on the dispute engaged by Husserl with Friedrich Schumann , and especially with his paper entitled “Zur Psychologie der Zeitanschauung” (Schumann 1898) , which played a crucial role in Meinong’s elaboration of objects of higher order . Husserl’s debate with Schumann sheds light on the originality of his arguments against nominalism.
For the sake of precision and clarity, a brief remark is in order here. Husserl distinguishes three notions of abstracta in the II. LU (II. LU: 129–131 [I: 252–253]). First, one must firmly distinguish between individual real moments (contemporary tropes) with general ideal Species (II. LU: 157, 217 [I, 270, 309]; Rollinger 1993: 122). Yet individual moments are themselves of two kinds: on the one hand, the objective abstracta, e.g. the red color of the thing; on the other hand, the subjective, lived content whose apprehension constitutes the objectual red color. Both of these moments are real, but only the latter is reell, that is, immanent to consciousness, while the former is only intentional (II. LU: 129, 198 [I: 252, 297]). For our present concerns, one may discard the first two meanings (Species and objective abstracta), that is, one may focus only on “immanent determinations” (II. LU: 200 [I: 298]), and leave aside any consideration of their intentional apperception.

2.2. Schumann’s account of the distinctio rationis

Let’s turn to Schumann. His paper starts by adopting a conception of abstraction that is very intimately inspired by Hume. For Hume, the distinction, in the concrete idea of a globe of white marble, between the form and the color, is only a “distinction of reason”. We do not have a genuine idea of the form or the color alone: they are “undistinguishable”. Yet, “observing afterwards a globe of black marble and a cube of white, and comparing them with our former object, we find two separate resemblances” (Hume 1960, 25). The alleged abstract idea of “white” or “spherical” is thus nothing more than the group of resemblance that is evoked, by association, once a white object (respectively, a spherical object) is presented.
In his paper, Schumann embraces this conception of the “distinctio rationis” (Schumann 1898: 107):

In the simple qualities of colors, sounds, etc., various so-called modifications are distinguished in linguistic expression, such as, for example, in a sound its depth, its weakness and its softness, in a red and white shade its redness and its whiteness, and so on, although these modifications are actually nothing that can be perceived separately from those simple qualities and nothing that can be separated from each other realiter, and have therefore not inappropriately been described as features (Besonderheiten) of those qualities that exist only for a distinctio rationis. (Schumann 1898: 107)

Husserl cannot accept Schumann’s conception of abstraction. His objections are twofold.

2.3. Husserl’s first objection: a phenomenological mistake

The first, well-known objection is nothing but a refinement of the one he addresses to Hume. Like Hume, Schumann “substitutes” another content to the original one (II. LU: 197 [I: 297]): it is a phenomenological mistake (Smith, A. D. 2008: 96) to replace the evident content of a perception (the moment of red) with another, missing one (alleged relations of resemblance) (Rollinger 1993: 117). Yet Schumann forces Husserl to go one step further. While debating with Meumann (1893; 1894), who states that abstract parts, such as intensity, can appear in a “relative separation” (relative Absonderung) from the sound (Meumann 1893: 504), Schumann gives a new solution to the problem of the distinctio rationis. He indeed rejects Meumann’s account, asserting that this would transform abstracta into “actual parts”, “wirkliche Theile” (Schumann 1898: 142). Yet Meumann, according to Schumann, is not entirely wrong in observing the relative separation of the partial contents. Even though the contents themselves are not intrinsically separated, they are brought into separation by an act of judgement:

“To bring to consciousness in relative separation” means at first only: to judge relatively separately. If, for example, we make a judgment once only about the intensity relation, the second time only about the quality relation, the third time only about the time relation of two sensations, the content of the sensation can be exactly the same in all cases, only different judgments are evoked. (Schumann 1898: 143)

Hence, it is only in the post hoc act of judging that the contents, which are not “actual (wirkliche) partial contents” (Schumann 1898, 144) in the original phenomenon, are apparently isolated.
In the LU, Husserl rejects Schumann’s “hypercritical” objections (II. LU: 200–201 [I: 298–299]). The distinction between the judgment and the experience does not preclude the judgment from being true, and this is in particular the case when it is evident. An evident judgement depicts the authentic state of affairs: if I judge with evidence that moments like colors or intensities do belong to my presentation—and this is the case—then I must admit that these partial contents are actual abstract parts of the original experience. The existence of a post hoc judgement thus does not modify Husserl’s argument: on the contrary, the phenomenological evidence of the existence of immanent abstract parts is reaffirmed with more clarity.

2.4. Husserl’s second objection: mereological nihilism and the ruin of psychology

Let’s now turn to Husserl’s second objection, which is even more interesting in our perspective, and is regularly overlooked in the literature . Husserl asserts that the radical Humean conception endorsed by Schumann “would render all psychologies impossible” (II. LU: 205 [301]). Why is so? Because Schumann’s position actually leads to mereological “skepticism” (II. LU: 205 [301]), or, to put it in in contemporary terms, to mereological nihilism (Varzi 2019): in the psychological sphere—let’s recall that I here consider only the immanent, reellen, contents—there would be no part of any sort and consciousness would therefore be mereologically atomic. In turn, such nihilism ruins the epistemological basis of psychology, since a science of lived experiences deprived of its mereological tools is an impossible task, as the V. LU shows (Mulligan and Smith 1988: 154). This consequence is obviously inacceptable: hence, Husserl’s argument works as a reductio ad absurdum which reveals the flaws of Schumann’s account.
Let’s study in detail this accusation of mereological nihilism, which is thus at the core of Husserl’s argument. This is assuredly not Schumann’s explicit position. Even though the latter rejects the existence of abstracta as authentic “partial contents” (Schumann 1898: 144), he also acknowledges the existence of “actual parts” (“wirkliche Theile”) (Schumann 1898: 130–131). Yet, Husserl emphasizes that the arguments used by Schumann to deny the existence of abstract parts necessarily lead as well to the rejection of concrete ones. Why is so?

2.5. Schumann’s principle of salience and its consequences

Schumann’s main objection against the existence of abstracta is based on an assumption that I would call the principle of salience. This principle states that being a part means appearing as a part in an intuitive fashion. For Schumann, this principle originates in his faithfulness to the testimony of “internal perception” (Schumann 1898: 144): in case such salience is not found, speaking of parts is arbitrary.
The first application of this principle is precisely to deny the existence of wirkliche Theilinhalte. Indeed, the white moment of a square, for instance, is interwoven with the other contents (in particular, extension). As a result, for Schumann, if one wants to remain faithful to internal perception, what appears is uniquely the whole phenomenon: the abstract parts are not phenomenologically salient, since the white square is an “inseparable (untrennbare)” or “complete (vollständige) unity” (Schumann 1898: 112, 130). Since abstracta are not salient, they should not be regarded as authentic contents at all. As we saw, for Schumann, it is only in post hoc judgements that these moments are relatively separated. As a result, abstracta are mere fictions, but nothing realiter.
Yet, the principle of salience has far-reaching consequences for concrete parts as well, and, to begin with, for intuitively undetached parts, that is, concrete parts that are fused with others. This is for instance the case for the right part of a square which is uniformly colored. For Husserl, such part is obviously an independent one (a concretum) (III. LU: 244 [II: 14]), even though it is not separated in the phenomenon. Yet, Schumann, appealing again to the salience principle, asserts that those undetached parts are as fictitious as are abstract ones:

I would like to point out that an arbitrarily shaped surface of completely uniform coloration, e.g. a square one, is first of all a complete unit according to the statement of inner perception. The parts, into which one can think such a unity broken up, are fictitious (fingierte) parts. (Schumann 1898: 130)

His reasoning runs entirely parallel in both cases: the undetached right part of a white square is not isolated in the original phenomenon. It is plain that I can focus my attention on this part, so it now appears as if it were isolated. Yet, Schumann understands this operation as a modification of the original state of affairs, which produces a new experience. On the contrary, in the primitive content, the right part is not manifest, and, in compliance with the salience principle, cannot be considered as a wirklicher Theil of the whole square—hence its status of fiction, of mere subjective creation.
Until now, Husserl has only followed Schumann’s assertions. Yet, in the second part of §38, he goes one step further and claims that Schumann, if he remains consistent with his line of thought, should also reject the existence, “at first unassailed” (II. LU: 203 [I: 300]), of the detached parts. It is usually assumed that, say, a white square, is salient. Yet, is not this salience the product of some subjective activity? What really appears is the whole visual field: within the latter, the white square is only isolated through the subjective means of eye focus and attention. Again, the original phenomenon is transformed into a new, distinct experience. The fact that the white square is separated in this derived phenomenon does not prove that it was a wirklicher Theil in the first place. On the contrary, the primitive, authentic, experience was a complete, unseparated, unity. As Husserl puts it:

If we hold more strictly to the contents, then in each case the privileged content is only as surrounded by an unclear, completely chaotic mass, which is not separated from it, but interwoven with it [so ist jeweils der bevorzugte Inhalt nur wie mit einer von ihm nicht abgetrennten, sondern mit ihm verwobenen, unklaren, völlig chaotischen Masse umgeben], a fringe, a “halo,” or whatever one may now call the unnameable. (II. LU: 204 [I: 300-301, trans. modified])

Hence, in virtue of the salience principle adopted by Schumann, it must be concluded that even intuitively detached parts are actually fictitious. The very same reasoning which showed that abstract as well as undetached parts were mere fictions reveals that even the alleged isolated parts are actually fused with the total content of consciousness, and are thus separated only in virtue of a special subjective emphasis.
Husserl is thus entitled to complete his demonstration. Schumann’s viewpoint necessarily leads to mereological “skepticism”:

If we persist in the skeptical direction, we shall have to doubt whether there are parts of any sort; and in consequence whether there is even a plurality of concrete contents, since ultimately (if we may still presume to judge the matter) the contents which appear in co-existence and succession are always in a manner unified. (II. LU: 205 [I: 301])

2.6. Formal ontology as the basis of Husserl’s rejection of the principle of salience

Husserl careful reconstruction of Schumann’s argument helps to identify the flaw in his reasoning. It is obviously the principle of salience, which guided his objections against both abstract and undetached parts, that is in question.
Yet, as we saw, Schumann’s defense of this principle was rooted in his will to remain faithful to internal perception and to escape arbitrariness in the partition of psychological phenomena. In this respect, how is it possible to build a concept of parthood that avoids, at the same time, the principle of salience and arbitrariness?
It is precisely the formal-ontological instruments of the III. LU that help Husserl to tackle such aporia. The major step he accomplishes here is to, so to speak, unphenomenologize mereological issues: to be a part is not a matter of subjective salience, on the contrary, it depends only on the objects at stake. As a result, the concept of parthood must be freed of any reference to subjective phenomena and regarded as a purely ontological notion.
In particular, the differences between detached and undetached contents, fused and separated contents, and the like, are merely subjective and must be firmly distinguished from the purely ontological difference between concrete and abstract contents (III. LU: 248–249 [II: 16–17]). The independence of a content does not depend in any way on the manner it is presented to consciousness, as isolated or fused. It is only in virtue of its nature that such-and-such object is independent or not. An object does not become non-independent because it is intuitively given as entangled with others, nor does it become independent because it is intuited separately. As a result, Husserl’s mereological concepts are indifferent to “phenomenological facts” (III. LU: 248 [II: 17]). It is the “intrinsic nature” of the contents, but not “the manner in which they are given” (II. LU: 220 [I: 311]) that accounts for the difference between abstract and concrete:

No reference back to consciousness is therefore needed, no reference to differences in the “mode of presentation,” to determine the difference between “abstract” and “concrete” which is here in question. All determinations which make use of such a relation, either represent an incorrect, misguided confusion with other notions of “abstract,” or are merely subjectively slanted expressions of a purely objective, ideal state of affairs. (III. LU: 236–237 [II: 10])

Yet this ontologization of mereology, which is accompanied by its correlative formalization, as we saw in the first part, does not prevent Husserl from addressing material issues. In fact, the exact opposite is true. The formal-ontological concepts of abstract and concrete objects can be applied to immanent contents. The latter are indeed nothing more than a special region of objects. It is true that the region of lived experiences (Erlebnisse) is opposed to the region of things (Dinge), that psychological contents and physical bodies belong to two distinct spheres of being. Yet an “object” (Gegenstand) does not have to be a “thing”: an immanent color or form is a genuine object, even though this may sound “disturbing” (II. LU: 219 [I: 310]). Husserl could not have said it more clearly: “immanent contents are only a special class of objects” (II. LU: 218 [I: 309]). In this respect, they are subject to the laws and concepts of formal ontology, in particular the abstract vs concrete distinction.
It is only at this stage that Husserl is able to reject Schumann’s principle of salience without falling into the trap of arbitrariness. That A is a part of B, or that A is abstract or concrete, is only an ontological or objective matter. This still holds (since A and B can be any object, in virtue of the formal character of these predicates) for immanent contents, as a materialization of mereological concepts. There is thus no arbitrariness in the existence of mental parts, or in the abstract or concrete character of psychical contents.
As a conclusion, Husserl’s debate with Schumann perfectly illustrates what I called in the introduction of the paper an up and down movement. The basis of the problem of abstraction is psychological; yet Husserl, in order to defend his position against empiricist objections, needs first to elevate the concepts at stake to a formal level, before coming back to the primitive issue with new, original insights. The relationship between the II. and the III. LU is thus now greatly clarified: the Second Investigation is not only the basis of the formalization that the Third operates (III. LU: 225 [II: 3]); it actually requires, in its own critical perspective, its main concepts and results.

  1. Conclusion: the up and down movement applied to Gestalt qualities

To conclude this paper, I would like to show that the up and down movement that was unveiled regarding Husserl’s treatment of abstraction is also reproduced regarding another very important issue at stake in the III. LU that has not been mentioned yet, namely the one of Gestalt qualities . In fact, Husserl’s replicates, vis-à-vis the issue of synthesis, the very process of unsubjectivization that we studied for analysis.
His main discussion on this subject is with Meinong. We saw that Husserl takes up Meinong’s vocabulary of founded and founding contents. Yet, this fact must not conceal the essential differences between their accounts. It is well known that von Ehrenfels, in his seminal paper on Gestaltqualitäten, depicted such quality (e.g., a melody) as being a “positive element of presentation” (von Ehrenfels 1890: 262) irreducible to the mere sum of the sensations at its base (von Ehrenfels 1890: 250). Yet he remained ambiguous (Fisette and Fréchette 2007: 90) on one of the most problematic issues, that later led to the division between the Graz and the Berlin schools: is the Gestalt quality given in the presentation, as a sensed quality, or is it the result of an intellectual production?
For Meinong, as is well known, the latter option must be embraced. The form is not “given with” its basis, but is the “product” of a specific “generation” (Hervorbringung) (Meinong 1891: 247). He reasserts this position in 1894, stating that an “psychical act of synthesis” is required to obtain the presentation of a plurality (Meinong 1894: 366; Fisette and Fréchette 2007: 104).
Husserl, even though he acknowledges—in fact independently from von Ehrenfels —the existence of Gestalt qualities (that he labels “figural moments” in PA) (Husserl 1970: 203; Husserl 2003: 215), cannot agree with Meinong’s account. Contrary to mere collections, which are purely “categorial forms”, wholes like melodies are “sensuous” (III. LU: 282 [II: 38]). This implies, for Husserl, that they are not produced by specific acts of the understanding—contrary to the categorial apprehension of aggregates—but are immediately sensed like qualities. Yet, in this context, if not an intellectual synthesis, what does account for the unity of these wholes? What is the difference between the isolated, separated existence of people (a mere sum) and their unification into one crowd?
Here the mereological concepts of the III. LU enter the scene: for independent parts (people, for instance) to be gathered into a whole, a specific “moment of unity” is required in addition to the primary constituents (III. LU: 234 [II: 8]). This moment is itself an actual part of the whole. Yet it is precisely a non-independent one: the moment of unity is founded on the basic contents as their “combinatory form” (III. LU: 278 [II, 35]). Hence Husserl’s formal definition of a whole—“a range of contents which are all covered by a unitary foundation without the help of further contents” (III. LU: 275-276 [II, 34, trans. modified])—is fulfilled (Vassiliou 2010: 423), and this suffices to account for the whole-ness of the crowd, the melody, and the like, without appealing to Meinong’s production theory .
It thus appears that the issues of abstraction and Gestalt qualities are treated in a parallel manner by Husserl. In both cases, we observe an unsubjectivization of the fundamental concepts and theses, then followed by a reintroduction of these newly formed ontological notions into the original, psychological field. Regarding abstraction, this unsubjectivization was achieved through the rejection of Schumann’s salience principle and his distinction between actual and fictitious parts; regarding Gestalt qualities, through the denial of Meinong’s production theory. In the first case, it is the existence and the nature of parts that no longer refer to psychological contingencies; in the second case, it is the existence and the nature of wholes that no longer depend on subjective activities. It is only in virtue of such formal-ontological reassessment that Husserl is able, in a second moment, to address the initial psychological issues at stake.
As a result, Husserl’s mereology owes a significant part of its value to its applications. It is not only a substantial piece of knowledge in itself, or a concrete illustration of what formal ontology should be. It is also an essential, operational instrument to propose fresh interpretations on traditional issues, in particular in the field of psychology. The existence of this up and down movement of formalization and materialization is thus not paradoxical: rather, the ascent to formality and the descent to materiality go hand by hand.

Alexis Delamare
2 place Barthélémy
76000 Rouen

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