The final synthesis: The implications of the natural philosophy contained in the Opus postumum for the question «What is a human being?»
Pedro Jesús Teruel[1]
Universitat de València
ORCID: https://orcid.org/0000-0003-0281-1811
DOI: 10.24310/nyl.19.2025.20334
Abstract: Kant’s thesis concerning the physical correlate of transcendental matter—proto-matter, cosmic or elementary matter, ether—which is the backbone of the Opus postumum, points to the pre-phenomenal foundation of the unity of the real. This foundation is consistent with a speculative hypothesis, ventured in the Critique of Pure Reason, concerning the original unity of body and soul. From the point of view of self-curing, this is consistent with Kantian approaches to the nurturing of human dispositions. Three of these are highlighted here: Kant’s strictly physiological treatment of mental illnesses, his statements on philosophy as exercise for the body, and his notion of dietetics. On the basis of this constellation of arguments, I propose a way to overcome the alleged Kantian dualism that finds its systematic axis in the notion of «mood» (Gemüt).
Key words: Kant; mind-body problem; self-curing; proto-matter; Gemüt; Opus postumum.
La síntesis final. implicaciones de la filosofía natural contenida en el Opus postumum para la cuestión «¿Qué es el ser humano?»
Resumen: La tesis kantiana relativa al correlato físico de la materia transcendental –protomateria, materia cósmica o elemental, éter–, que vertebra el Opus postumum, apunta al fundamento pre-fenoménico de la unidad de lo real. Dicho fundamento concuerda con una hipótesis especulativa, aventurada en la Crítica de la razón pura, concerniente a la unidad originaria de cuerpo y alma. Desde el punto de vista de la cura de sí, resulta coherente con los planteamientos kantianos en torno a la cura relativa a las disposiciones humanas. Subrayamos aquí tres de ellos: el tratamiento estrictamente fisiológico de las enfermedades mentales, las afirmaciones sobre la filosofía como ejercicio para el cuerpo y la noción de dietética. Sobre la base de esta constelación de argumentos, planteamos una superación del pretendido dualismo kantiano que halla su eje sistemático en la noción de «ánimo» (Gemüt).
Palabras clave: Kant; problema mente-cuerpo; cura de sí; protomateria; Gemüt; Opus postumum.
Recibido: 25 de julio de 2024
Aceptado: 28 de octubre de 2024
1. Introduction: A retrospective investigation
The question of the human being occupies a specific place in the Kantian conceptual edifice. The three questions in which every practical interest of reason can be found—namely: «What can I know?», «What must I do?», «What am I allowed to hope for?»—can be redirected to a fourth: «What is a human being?» (Logik, AA 09: 25; letter to Carl Friedrich Stäudlin of 4 May 1793, AA 11: 429). And yet the Kantian system itself seems to have locked the possibility of an answer behind seven doors.
The distinction between the phenomenal and the noumenal relegates knowledge of the essence of the human to its objectifiable aspect, determinable in space and time with the help of pure concepts. Certainly, all determination proceeds from a transcendental subject and is rooted in the self. The notion of transcendental consciousness encompasses not only transcendental apperception, but also the conditions of reflection. In apperceptive and reflective acts, however, transcendental consciousness is a non-objectifiable condition of self-affection: it is always presupposed, so that any further determination always involves a further step backwards, an eye that looks without being seen. It happens as in René Magritte’s painting Not to Be Reproduced: the image that the mirror returns is that of a contemplator who fails to capture his own face (see Magritte, 1937). In an analogy coined by Kant to illustrate the impossibility of self-knowledge: the subject cannot observe himself in the mirror while he sleeps (AA 20: 309).
Kant himself expressed this convincingly, once the guiding orbits of the Copernican turn had been completed, in 1791:
«I am conscious of myself» is a thought that already contains a double I: the I as subject and the I as object. How it is possible that I, one who thinks, can be for myself an object (of intuition) and thus distinguish myself from myself, is quite impossible to explain, although it is an indubitable fact. But it reveals a capacity so far above all intuition of the senses that it brings with it, as the basis of the possibility of an understanding, a complete distinction from every animal to which we have no reason to attribute a capacity to say «I» to itself, and which is prolonged in an infinity of spontaneously formed representations and concepts. However, this does not imply a double personality, but only that the I—the I which I think and intuit—is the person, while the I of the object which is intuited by me is, like other objects outside me, the thing. (Preisschrift, AA 20: 270)
Juan Miguel Palacios has alluded to human beings’ moral knowledge of themselves, necessary and at the same time impoverished, as the scene of a disconcerting reduction. This would be an aspect of the abyss between the theoretical and the practical that so disturbed Kant himself, and which derives from his clear distinction between the phenomenal and the noumenal, as demanded by the structure of transcendental idealism:
By declaring things in themselves to be unknowable, transcendental idealism must reduce the person to the spectacle of his mere phenomenal grimace; and by rejecting the possibility of even an analogical knowledge of reality itself obtained from its phenomena, that grimace must always appear inexpressive and disconcerting. Kant, perplexed by it, came to think that it hides its secret in man himself and that there is no theory to decipher it. So that only a madman like Don Quixote can say: «I know who I am.» (Palacios, 2003: 39)
Palacios is right to point to the distinction between phenomena and noumena as the origin of the transcendental gap that prevents an account of self-knowledge. In the light of this original wound, it is understood that the anthropology lessons that Kant gave from the winter semester of 1772-1773 onwards are marked by empirical and pragmatic considerations. I have previously argued that these lessons are not the answer to the question «What is a human being?», but rather to another question: «How does man exist, live and act?» (Teruel, 2008: 243-245).
Kant himself emphasizes this pragmatic modulation in his lectures. But here the boundaries between the legitimately determinable and the theoretically unknowable begin to blur. In the anthropological lectures collected by Starke around 1781, the following is pointed out: «I must know what access I can have to human dispositions (zu den menschlichen Gesinnungen) in order to produce resolutions; for this, knowledge of the human being can give us a basis» (Starke, 1831: 7). In this sense, «anthropology is to morality what geodesy is to geometry» (V-Mrongovius, AA 25: 1210-1211).
How is it possible to draw up a cartography of the human that serves as a moral compass for action (moralische Triebfeder)? Elsewhere I have attempted a systematic answer by referring to three cartographic areas—material-physiological, psychological-social/individual and transcendental-moral—and their correlates in different disciplines: empirical anthropology in a physiological key; empirical anthropology in a pragmatic key; transcendental anthropology and dogmatic-practical pneumatology (Teruel, 2008: 246ff.). Here I would like to try out a complementary perspective, using a retrospective method.
I will begin at the end: with Kant’s final attempt at synthesis and to overcome the divisions that he himself detected in his system, divisions that are reflected both at the general level—between the theoretical and the practical—and at the natural-scientific level—the transition from the metaphysical principles of natural science to physical science—and at the anthropological level in the mind-body problem. The Opus postumum [hereafter, OP] presents a thesis on proto-matter that points to the pre-phenomenal conditions of the real and its cognitive anticipations. In the second part, I will link this thesis with Kant’s hypothesis, set out in the Critique of Pure Reason [KrV], concerning the conditions for a possible link between the phenomena of the body and its noumenal motives. We will then see, in the third part, how both of these explanatory frameworks attempt to provide a theoretical basis for a non-dualistic anthropology, which I will present by focusing on two significant passages: Kant’s strictly physiological treatment of mental illnesses, and his view of philosophy as medicine for the body. I will then show how the term that psychosomatically underpins this non-dualist anthropology is «Gemüt», which is translated as «mood». I will conclude with some remarks on self-curing, which will take us back to the Stoic sources of Kant’s thought.
The itinerary of our retrospective investigation is thus arranged. The result will suggest a rethinking of the alleged Kantian dualism and the quixotic reverie of answering the most radical question: «Who am I?»[2]
2. The pre-phenomenal condition of world unity
The notion of matter undergoes diverse modulations in Kant’s work. I have classified these modulations, in his pre-critical phase, under the denominations «determinable matter», «configuring matter» and «determined matter» (Teruel, 2024: 87-89). In his critical phase, the first and the third are maintained; while the second, at the behest of the transcendental shift, becomes «determinant form» (Teruel, 2024: 90-92). Matter appears as the necessary substratum of phenomenal determination, «substantia phaenomenon», as necessary as it is unknowable: «a mere something, of which we could not even understand what it is even if someone could tell us» (A 277/B 333; cf. Kant’s letter to Carl Leonhard Reinhold of 12 May 1789, AA 13: 37).
However, a need to characterize this pre-phenomenal substratum emerges, by way of a gap in the uniform coherence of the transcendental fabric. The Critique of Judgement points to «matter, or the primordial substratum which is reworked by Nature» (AA 20: 215) and to the self-organization of Nature in the production of species from this unitary origin: a «daring adventure of reason» which is not incompatible with the transcendental perspective, but which does not allow itself to be empirically revealed (AA 5: 419, footnote on pages 419-420). Transcendental matter would be the substratum of phenomena, not according to their determinacy—that would be Nature—but according to their determinability.
Both in his pre-critical period and after his critical turn, there are numerous occasions on which Kant expresses his conviction that changes on the phenomenal plane must be due to heterogeneities on the plane of transcendental matter. This variety must already be supplied to sensation: «I could not abstract from only one aspect in the previous proof [the transcendental deduction of the categories, PJT], namely, that the multiplicity offered to intuition must already be given before the synthesis of the understanding and independently of it; it remains to be determined here, however, how this comes about» (B 145). This multiplicity implies not only a quantitative heterogeneity, but also a dynamic heterogeneity. Thus matter must be endowed with force, for the dynamics of natural forces must be given, and this underlies the second and third analogy of experience under the concept of action: «Where there is action and, with it, activity and force, there is also substance, and only in substance is the seat of that fruitful source of phenomena to be sought» (A 204/B 250).
This dynamic heterogeneity is translated into a phenomenal world, and articulated in a regular way, which offers a constant frame of reference. How is this possible? This is the question Adickes (1929: 75) adjectivized as «Herbart’sche Frage», referring to how Johann Friedrich Herbart had individualized phenomenal constancy as the problematic crux of transcendental idealism.
One line of argument is devoted to transcendental research on the ontological presuppositions that allow the transition from the metaphysical principles of natural science to physics in the OP. Of these, we are particularly interested in those contained in the fourth and fifth collections, written before the end of 1799 and structured with a significant conceptual coherence. Elsewhere, I have read the OP as a continuation of the project undertaken in the Metaphysical Foundations of Natural Science (1785), in keeping with my interpretation of the doctrine of the ether as a thesis with ontological validity (Teruel, 2024: 94, note 5; 94-100, and note 13).
Proto-matter (Grundstoff), elementary or caloric substance (Elementarstoff, Wärmestoff), or ether, constitutes, in this final synthesis, the pre-phenomenal foundation of quantitative and dynamic heterogeneity. Its aggregations or lumps (Klumpen) and its regular movements or pulsations (Klopfungen) give rise to the oscillations (Schwankungen, undulationes) through which heterogeneous configurations emerge and, with them, the variety supplied to sensation and transcendentally elaborated as phenomena (fifth collection, July 1797-May 1799, AA 21: 533). This proto-matter is to be postulated as necessary, since it is «causalitas phaenomenon» (AA 21: 525) and thus an «elementary substance in the strictest sense of the word» (AA 21: 357).
The epistemological modulation of the proof is specified, between May and August 1799, in Kant’s «Remark» on the sixth folio of the fifth collection (E5, L5, AA 21: 538-544). First, proto-matter is the basis of affection, since an empty space cannot be the object of experience (AA 21: 547, 549-550, 573, 583, 590). Secondly, objects are interconnected by dynamic regularities, which requires an extramental foundation (AA 21: 538). To this is added a reductio ad absurdum concerning elementary forces: if attraction and repulsion did not have their correlates in a pre-phenomenal matter, they would annihilate each other (AA 21: 538-539). From the fact that the a priori form of space does not remain eternally empty and equal to itself, and that its sensible fullness presents a coherent internal articulation, one must infer—indirectly and negatively—the existence of original matter (AA 21: 539-540, 544, 546-548). This triple foundation shows the distance between Kant’s notion of ether and the concept used in the works of Antoine Laurent Lavoisier, Isaac Newton and Leonhard Euler (see Teruel, 2024: 97, notes 8 and 9).
Compared to this primary matter, all other substances are secondary matter (fifth collection, May-August 1799, AA 21: 605; L7, AA 22: 92-93). Thanks to secondary matter, it is possible to move from the metaphysical principles of natural science, the source of which is to be found in the Transcendental Analytic of the KrV and its development in the homonymous work of 1785, to physics, without making any conceptual leaps over an impassable abyss. Hence Kant links this bridge with what he considers to be a new schematism (L9, July-October 1799, AA 22: 263, 265; L11, August 1799-April 1800, AA 22: 487).
This thesis encapsulates the extreme effort of Kantian systematization. Projected retroactively, it points to the ontological foundation of the hypothesis about the original unity of the phenomena relating to the human body, and of the transcendental presuppositions concerning the plane of action. Indeed, proto-matter cannot be understood in mechanistic terms: these are only applicable at the level of the phenomenon. A fortiori, the ontologically reductionist interpretation of the real, which restricts it to its mathematical-geometric dimensions and deterministic dynamics—namely materialism—cannot be extended beyond phenomenal determination; the contrary would be tantamount to dogmatism (B XXX). Proto-matter points to the prior ontological horizon.
This horizon coincides with the hypothesis that Kant puts forward in his chapter on paralogisms. We are now ready to elucidate the implications of this post-synthesis in Kant’s approach to the human being.
3. A speculative hypothesis on the original unity of soul and body
The chapter devoted to the paralogisms of pure reason is structured by a fundamental thesis: the transcendental mirage (transzendentaler Schein) produced by pure reason—as expressed, for example, in Wolff’s special metaphysics of the soul—is due to a surreptitious confusion between, first, thinking of transcendental apperception as a condition of the subjective possibility of synthetic activity and, second, knowledge of the soul as an ontological and extramundane substratum of this activity. It is understood, then, as ontological determinations that are only logical-functional (see Andaluz, 1999: 375ff.). For this purpose, the pure concept of substance slips into the major premise of the reasoning, while, in the minor premise, this concept is associated with a mode of existence in time (see White Beck, 1960: 265-266).
The first edition contains a highly speculative hypothesis which is of interest here. The second paralogism, relating to the categories of quality, concerns the simplicity of the subject. It expresses the absolute unity of the apperception that makes knowledge possible, from which the simplicity of the soul and its incorruptibility have been deduced. This simplicity exists, but it does not belong to any alleged metaphysical subject of inherence—this is the criticism—but rather to the logical subject of representation. The ontological projection into incorruptibility is thus a transcendental mirage. And yet we cannot rule out the possibility that the noumenal substratum of the thinking subject converges, in its essential structure, with its phenomenal manifestation. Under this supposition, «that very thing which, from one point of view, we call corporeal, would be, under another and at the same time, a thinking being» (A 359). This would be an original unity. The transcendental specification of our knowledge would have just left us with the phenomenon in sight, giving rise to a conceptual enigma—the mind-body problem—which, however, is only quoad nos: if we could access the thing-in-itself, we would realize that the duality is resolved monistically.
This hypothesis evidently has no place in transcendental idealism. In the second edition of the KrV, it is in fact eliminated, together with the neat quadripartite structure of the paralogisms, for reasons of improved exposition (B XXXVII). Kant keeps unchanged his thesis according to which there is no basis for making intelligible the connection between the soul (the mental) and the material (the bodily). In response to an anthropology published by Ernst Platner, which aimed to «consider body and soul together in their reciprocal connections, limitations and relations» (Platner, 1772: XV-XVII), Kant writes to Marcus Herz that «the subtle and, in my opinion, eternally futile investigation into how the body’s organs are connected with thought» should be omitted entirely (letter to Herz at the end of 1773, AA 10: 145). This thesis remains in place during his critical period, and finds its most precise formulation in his epilogue to Sömmerring’s work On the Organ of the Soul, published in 1796. Elsewhere I have discussed the structure of Kant’s response and how he maintains his sceptical veto on the intelligibility of such a link (Teruel, 2008b).
This veto concerns the possibility of making intelligible the link between the brain and the mind and, more generally, between the bodily and the mental. Nevertheless, such a link exists. The bodily is connected to the mental through dispositions whose relevance for moral orientation is enormous. Hence the reference to access to human dispositions in the quotation from the anthropological lessons collected by Starke, reproduced above in the introduction of this article. The orientation of one’s own maxims to the moral law finds its original source in affective dispositions: from moral sentiment to conscience, love and respect for duty; these are aesthetic instances that enable the mind’s receptivity to the concepts of duty, as they are presented in 1798, in the second part of The Metaphysics of Morals (AA 06: 399-403). The aesthetic experience reveals, in its modulation of the mathematical sublime and the dynamic sublime, an autonomy and an elevation above Nature (KU, AA 05: 246, 261), which are discovered as «suprasensible determination in us» (AA 05: 257). In doing so, however, the gap between nature and freedom has not yet been bridged, but our awareness of their heterogeneity has been sharpened (see Dörflinger, 2022: 125-126).
Thinking about this link must be possible. In my opinion, this can take place in three modulations. The first is ontological: it points to the original condition of the union between the different dimensions of the human in a proto-matter that is not intelligible in materialistic terms. The second is biological-evolutionary: it develops on the horizon that is envisioned by Kant himself in his reference to the «audacious adventure of reason». The third is practical: it unfolds in the spiritualizing action of matter that takes place through the exercise of scientific and artistic activity. The second and third are the subject of two complementary contributions (see note 2); we shall deal here with the first.
These modulations have a historiographical aspect. Kant’s project of mapping the transition from the metaphysical principles of natural science to physics presents projections that go beyond empirical physics; they connect with the dynamics of the living and the thinking. Dario Drivet (2022: 147-152) rightly highlights the chronological and thematic connections between the problem of the transition from the sensible to the suprasensible in the Critique of Judgement, Kant’s consideration of the dynamic organization of the chemical in his epilogue to Sömmerring’s work, and his interest in the approaches of Luigi Galvani and Eramus Darwin, issues that converge in the problematic proper to the OP. It is significant that, on the first page of the preparatory sketches leading to the aforementioned epilogue, Kant acknowledges his «strong tendency» to consider a «transition from the doctrine of the soul to physiology (to the nature of vivified matter)» (AA 13: 398).
In what follows I will outline three ways in which Kant explores the link between the mental and the bodily. I will focus on three aspects of human healing: the treatment of mental illness; care of the body, which is carried out through philosophical activity; and dietetics, which is seen as an extension of philosophy. We will thus retrace three decades in the development of Kant’s work.
4. The systemic unity of the human being
The doctrine of the interrelationship between the physiological and the mental is a common thread, no less real for its subtlety, in the philosophical itinerary of the philosopher from Königsberg. A close look at three writings published in different decades—the sixties, in his pre-critical phase, and the eighties and the nineties, in his critical period—is enough to persuade us of this.
The best strategy for remedying mental illnesses is not psychic treatment, but a physiological cure: in particular, measures to cleanse the digestive system and balance its processes. This is what Kant states in his 1764 work Essay on the Diseases of the Head (VKKK, AA 02: 270). It should be noted that this strategy will be effective in cases involving a physiologically rooted disorder, rather than the result of purely psychic patterns related to harmful behaviour; hence the main part of this work is devoted to a classification of mental illnesses. Kant takes up a digestive therapy for mental ailments from a proposal made by Johann August Unzer (1761) in his weekly journal The Physician. In three articles, respectively published in issues 150, 151 and 152 of this journal, Unzer discusses the close link between mental processes and the digestive system. In doing so, he draws on observations from an extensive secondary literature, ranging from ancient authors such as Hippocrates to more recent ones such as Herman Boerhaave and Jan Van Helmont (Unzer, 1761: 317). Both the Kantian indication and the Unzerian thesis find their psychophysical foundation in the profusion of nerve endings surrounding the digestive system, the observation of which led John Newport Langley to classify them as an enteric section of the autonomic nervous system. Subsequent research has supported their overlap with the central nervous system, conveyed by sympathetic and parasympathetic innervations (see Kandel, 1996: 766). Elsewhere I have identified the Kantian source and set out the foundations of Kant-Unzer’s thesis, as well as its relation to the functional perspective that led to the modern consolidation of physiology (Teruel, 2013a; 2022).
Just as physiological treatment contributes to mental health, so philosophical work promotes bodily health. This is the thesis of the speech with which Kant took office as rector of the Albertine University of Königsberg (1 October 1786), as well as the speech he delivered on the occasion of his re-election (4 October 1788). (Since Mendelssohn died on 4 January 1786, and in view of his leading role in the Rektoratsrede, I am inclined to the earlier dating (see Reicke, 1881).) The speech was entitled De Medicina Corporis, quae Philosophorum est / Regimen mentis quod Medicorum est. On the influences exhibited by the text—in particular, that of Ehrenfried Walther von Tschirnhaus—and its argumentative structure, which are of considerable importance for the range of issues we are interested in, various studies can be consulted (Brandt, 1999: 354ff.; 2007: 7-12; Teruel, 2014: 255ff.).
Insofar as it contributes to mental balance and to moderation in the sensible satisfaction of natural needs, philosophy is a powerful remedy for the ills of the body, and also facilitates their prevention. Accordingly, Kant criticizes medical schools that treat the human organism on the basis of an analogy with machines, as in the iatromechanism of Friedrich Hoffmann. These schools disregard «that admirable faculty of the feeling and moving principle called imagination», which can arrive freely and consciously exercised to moderate the «motions of the mind, called affections» (animi motus, quos affectus vocant), motions which in turn influence organic states (Rektoratsrede, AA 15: 944).
These reflections are projected into the past and into the future. On the one hand, they link up with the explicitly Rousseauian—and implicitly Epicurean—inspiration of the diagnosis of superfluous needs that are artificially promoted in social contexts, an issue addressed in the Essay on the Diseases of the Head (VKK, AA 02: 269). On the other hand, they prepare Kant’s characterization of philosophical work as an integral part of medicine and, more specifically, of dietetics. Drawing on his long-standing familiarity with the orientations of medicine and its resources, Kant forged his own classification of the medical disciplines in the 1790s. This appears in various reflections, consistently with the third section of The Conflict of the Faculties (1798).
Medicine—or, as he calls it, after Hippocrates of Cos, «the Hippocratic affair» (Refl 1544, phase w5, 1799-1800, AA 15: 967)—is structured into two strands. The first is made up of those disciplines that regard the organism as a set of physically determined processes (res naturales) and therefore deal with its disorders in a mechanical or chemical way: pharmacopoeia and surgery. The second, on the other hand, focuses on the psychic-physiological processes linked to the configuring force of the will (res non naturales); these allow the establishment of guidelines that do not require drugs or surgical intervention, as in dietetics and gymnastics. Pharmacopoeia and surgery make up therapeutics; dietetics and gymnastics make up hygiene. The sources for this classification include texts from the 1790s, including the 1796 Proclamation of the Imminent Conclusion of a Treaty of Perpetual Peace in Philosophy, and the aforementioned work The Conflict of the Faculties (e.g. VNAEF, AA 08: 414-415; SF, AA 07: 97-11). I have presented these sources systematically elsewhere (Teruel, 2014).
Dietetics is an eminently philosophical task, since the guidance of reason is responsible for the search for balance in the satisfaction of our needs in nutrition, as well as in rest and other aspects of life. Kant’s notion of dietetics («Diätetik») is closer to the Greek term «díaita», meaning tenor or kind of life, than it is to the Latin term «diaeta», meaning diet. Hence he even uses the expression «dietetics of thinking» («Diaetetic des Denkens»), which is immediately reflected in the notion of Gemüt (Refl 1105, phase q2, 1783-84, AA 15: 491).
Kant’s itinerary thus presents a coherent picture, sustained—from his pre-critical phase to his critical period—for more than three decades, in which the interaction between the physiological and the mental is approached from coinciding and complementary perspectives: therapy for the mind through digestive balance, bodily hygiene through philosophical work, and diet as a psychophysical exercise.
5. The notion of «Gemüt» as a systematic vehicle
All this shows the existence of a transversal sphere of intermediation between the different instances. If this interaction is to be real—and the above-mentioned research points to such a reality as an indubitable starting point—there must also be an ontological framework to convey it: mind and body could not exert any mutual influence if they were clearly differentiated realities. In other words, there must be a «two-sided» structure that makes it possible to bridge the eidetic heterogeneity of the bodily and the mental. This schema—no longer pre-ontic as in the case of proto-matter; nor transcendental because of the mediation between the category and the sensorially grasped—is a psychophysical schema and is to be found in the mind (Gemüt).
The notion of Gemüt occupies an unthematized and yet relevant space in the KrV. However, it is not until 1796 and Kant’s epilogue to Thomas Sömmerring’s On the Organ of the Soul that it is precisely defined, in a brief but substantial footnote (AA 12: 32). Gemüt is not understood as a substance of which metaphysical attributes can be predicated—the impossibility of which was explained in the section on paralogisms in the first Critique—but rather as the faculty that enables the integration of representations that are unified through empirical apperception, representations whose correlate is to be found in brain impressions.
It is worth noting that translating this term into different languages has involved a characteristic equivocity. Elsewhere I have analysed both its etymology and its different translations in the main languages of Kantian studies (Teruel, 2013b). It will suffice here to draw attention to the one-sidedness of the versions that always translate it as «mind». Insofar as the unification carried out involves not only intellectual aspects, but also volitional and affective ones, the translation will have to take this plurivocity into account. There are contexts in which the translation «mind» or «mood» corresponds to what is being exposed; this is generally the case in the KrV’s Transcendental Analytic.[3] In favour of the frequent translation as mind, one can cite the English term’s proximity to the semantic field of mood. On other occasions, the term relates to volitional or affective aspects, in parallel with the semantic shift towards the area of Erregung (see Teruel, 2021). In his aforementioned epilogue to Sömmerring’s work, and in a note indebted to the KrV’s Transcendental Dialectic, Kant indicates in brackets the Latin term for the notions in question: anima, for the metaphysical substance; and for the psychosomatic faculty, animus (AA 12: 32).
As the term is configured, Gemüt points to the framework that conveys the systemic interrelationship we are dealing with: a framework that allows aesthetic receptivity to the concepts of duty to relate to organic dynamics. Voluntarily oriented by the imagination, it conveys the implementation of moral maxims in the configuration of organic patterns and, with it, the curing of the body modulated by the exercise of the will. Since the 1780s, Kant developed this idea against the background of his conception of health as a balance between the vital forces and as regularity in the self-production of organic parts.
This characterization finds a powerful stimulus in his reading of John Brown’s Elementa medicinae (1780), where research such as Albrecht Haller’s on muscular irritability was collected, disease was characterized as an excess or defect of excitation or strength—sthenia or asthenia—and health was interpreted as mutual equilibrium or moderation. Kant reworked this idea from his Rector’s Address (1788) to The Conflict of the Faculties (1798), through the manuscript of Proclamation of the Imminent Conclusion of a Treaty of Perpetual Peace in Philosophy (1796). It is noteworthy that Brown’s influence is referred to, both in later writings (MS, prologue, AA 06: 207; Anth, AA 07: 255; letter to J. B. Erhard of 20 December 1799, AA 12: 296) as well as in passages found in loose sheets written contemporaneously with the OP (Refl 1539, AA 15: 963, 964; Refl 1544, AA 15: 967; Refl 1548, AA 15: 970, all dated by Adickes to the phase w5, 1798-1804), as well as in numerous fragments of the OP itself (OP, fifth collection, July 1797-May 1799, AA 22: 612; eighth collection, October-December 1798, AA 22: 176; tenth collection, August 1799-December 1800, AA 22: 300; eleventh collection, April 1800, AA 22: 469; first collection, December 1800-February 1803, AA 21: 71).
The spirit is the vehicle of this psychosomatic balance. Spurred on by his reading of Christoph Wilhelm Hufeland’s The Art of Prolonging Human Life (Die Kunst das menschliche Leben zu verlängern), which he received from the author himself on 12 December 1796, he wrote to Hufeland, alluding to his own project of developing a dietetics (which would crystallize in the corresponding section of The Conflict of the Faculties). This dietetics was to promote what Kant calls Macht des Gemüths (letter to Hufeland of 19 April 1797, AA 12: 157ff.). This is no longer the intellectual penetrative power of the mind; it is not merely the functional correlate of the metaphysically encumbered notion of the soul; it is not an idea of reason. Rather, it is the active exercise of organic moderation—in the manner of Brown—which presupposes an instance of psychophysical interrelation: it is the power of the mind.
In dietetics—restraint and abstinence, always in the right measure that allows the pleasures of life to be enjoyed—the configuring power of freedom is revealed: this is eleutheriology in action. Hence it occupies a crucial place in the cartography that interests Kant: the one that allows the transition from physiological to pragmatic considerations to take place. Attention (Aufmerksamkeit), which is the «immediate operation of the mind», unmittelbare Gemüthsoperation (SF, AA 07: 111), plays a decisive role in supervising the maxims adopted by practical reason—in detecting excesses and counteracting them by means of mental habits that revert to regulated physiological dynamics. Kant thus links up with the contemporaneous trends of empirical psychology found in the work of Johann Georg Sulzer, Jakob Friedrich Abel and August Friedrich Bök, who influenced Friedrich Schiller and German idealism (see Teruel, 2014: 227).
The active unification and integration of the psycho-physical, linked to the actual adoption of moral maxims and the forging of character, is the task of the mind (Gemüt) and not of the intellect (Verstand); nor, as in the Cartesian tradition, of mere conscious thought within the framework of cogitatio. The link between human beings’ moral, psychic and bodily aspects, which is based on a systemic unity, is thus emphasized.
6. Coda: Rethinking the Kantian image
The different levels of argumentation that we have retrospectively set out here take up the implications of the final synthesis conveyed by the OP. The transition sought in that final effort points to the need to show how the connection between transcendental matter and objective knowledge of Nature is possible in the world. The notion of proto-matter points to a pre-phenomenal structure that constitutes, in turn, the foundation of the unity of the physical and the psychic: a network of essential affinities from which the structuring of the objective unfolds. It is on the basis of this original unity, a condition for any possible cognitive anticipation, that the link between the different dimensions of the human can be intelligible. This is not a question of the connection between heterogeneous substances, but of the link between originally related realities. In the word «Gemüt» we have found the terminological vehicle for pointing to this space of intersection. The thematic aspects we have highlighted—including the physiological therapy of mental ailments, the philosophical hygiene of the body, and diet as psychophysical exercise—are all thematic indices of the original interrelationship. This is a different kind of knowledge from the objectively determining one, which is framed in the reflective search for a synthesis. Its sphere is that of a theoretical postulate: precisely that which Kant reserves for proto-matter in the OP.
With all this, Kant was merely continuing the thread of reflections he began in his youth. In his 1754 work The Question, whether the Earth grows old, weighed in physicalist terms, he had referred to the original unity as the «Proteus of Nature» (AA 1: 211-212). I have previously referred to the parallels that can be drawn between these considerations and the Suarezian theory of affinities (Teruel, 2024: 100-103). On this occasion I would like to refer to an older precedent.
The Stoic thesis according to which everything real is connected by intelligible ontological relations is well known: the reality of the Universe (κόσμος) is a whole transcended by order (λóγος) and, insofar as they are part of it, beings endowed with intellect possess seeds of this intelligible structure (λόγοι σπερματικὸς). For a Stoic like Marcus Aurelius in his Meditations (e.g. XII, 3), the dimensions of the human—body (σῶμα), vital breath (πνεῦμα), and intelligence (νοῦς)—are in a relationship that is not free of conflict but, nevertheless, is always capable of being brought back to the balance of an autonomous imperturbability (αταραξία). In this sense, and as Pierre Hadot and Martha Nussbaum have emphasized, philosophy is a form of integral healing.
The terms of the semantic field mentioned in the previous paragraph are well known to Kant, especially thanks to their respective Latin translations, with which he began to familiarize himself at the Collegium Fridericianum. Hence he alludes to the dietetic character of philosophy as something properly Stoic:
Stoicism as a principle of dietetics (sustine et abstine) thus belongs to practical philosophy not only as a doctrine of virtue, but also as medicine: it is therefore philosophical when the sole power of reason in the human being, consisting in dominating the sensible feelings by means of a self-given principle, determines one’s way of life. (SF, AA 07: 100-101).
This «determination of one’s way of life» links intellectual orientation with the channelling of the will and the power of the mind:
Incidentally, philosophizing, even without being a philosopher, is also a means of counteracting certain unpleasant feelings and, at the same time, a stirring of the mind which, when it takes place, brings with it an interest that is independent of external contingencies, and which, even if only as a game, is nevertheless vigorous and internal, and does not allow the vital force to be paralysed. Philosophy, on the other hand, which focuses its interest on the whole of the final goal of reason (absolute unity), brings with it a feeling of strength which to a certain extent can compensate for the physical weaknesses of age by a rational estimation of the value of life. (SF, AA 07: 102)
In September 1798, Christian Garve sent Kant a letter in which he described how philosophical work helped him to compensate for the symptoms of his illness (AA 12: 254). We may well suppose that this description must have met with his addressee’s profound acquiescence. And all this connects with the central axis of Kant’s thought: the forging of character. After all, «the foundation of a character is the absolute unity of the inner principle of one’s way of life (Lebenswandel)» (Anth, AA 07: 295).
The implications of the project contained in the OP, to which we have referred here in pursuit of one of its guiding threads, point to the ontological conditions of the real and refer, retrospectively, to investigations that point to the systemic interrelation expressed in the notion of Gemüt. In examining them, we have been interested not only in the letter of Kant’s system, but also in its problematic articulations which, like gaps in its argumentative fabric, point towards Kant’s concerns: towards the horizon of intelligibility which, although venturing beyond the limit of the «land of truth» won by transcendental idealism, Kant did not want to keep from reflection.
In a certain sense, we are all a mystery to ourselves. This is something that has been glimpsed since the beginnings of philosophy: for Heraclitus, «you will not find the limits of the soul by walking, whichever path you tread; so deep is its foundation» (DK 22 B 45). Hence only a madman like Don Quixote can say: «I know who I am.» And, despite everything, there is some possible knowledge. Kant circumvents his veto concerning the transcendental subject by shifting his focus of enquiry to the conditions of psychophysical interrelation. In doing so, he shows us an unfamiliar image, far from the dualistic stereotype and the gap between res cogitans and res extensa, which is deepened within the framework of mechanicism. His endeavour does not cease to be overly ambitious: it is, in a certain sense, a quixotic desfacer entuertos.
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Pedro Jesús Teruel
pedro.teruel@uv.es