Our point of departure: Kantâs Opponenten-Rede
In his 1912 biography, Kants Leben, Karl VorlĂ€nder accords âa recently published Latin speechâ a âsignificance not to be underestimatedâ for Kantâs perspectives in aesthetics (VorlĂ€nder 1986, 101f.). VorlĂ€nder is referencing the Opponenten-Rede that Kant held on 28 February 1777, on the occasion of the second half of the public disputation of Johann Gottlieb Kreutzfeld, who had recently been named Professor of Poetry at the University of Königsberg. As was then customary, Kreutzfeld was obliged to defend an inaugural dissertation before assuming his position. He did so in two parts. He presented the first part, âpro receptione (in facult. philos.)â, on 25 February 1777. The second part, âpro loco (profess. ordo.)â, he defended on the 28th. For the latter presentation, Kant served as the official âopponentâ drawn from the circle of faculty who would become Kreutzfeldâs colleagues. Kreutzfeld titled his two-part dissertation, Dissertatio Philologico-Poetica de Principiis Fictionum Generalioribus, that is: Philological-Poetical Dissertation on the General Principles of Fictions.
Kantâs response, which he wrote in longhand on the interstices of the print copy of part two of Kreutzfeldâs dissertation, has received little scholarly attention to date. One reason for this, among others, is that commentators concerned with aesthetic issues typically focus on the third Critique, the Critique of the Power of Judgment (1790). From the perspective of media theory, however, Kantâs early writings offer surprising insights into the interconnectedness of issues in aesthetics, epistemology, and the philosophy of perception. This is especially true of Kantâs Opponenten-Rede and its treatment of concepts such as optical illusion, perspective, and projection â a treatment that owes much to the mathematician, universal scientist, and inventor of diverse scientific instruments, Johann Heinrich Lambert. The discussion between Lambert and Kant reaches its acme in the question of the epistemological status of a technique-generated âstanding appearance [Schein]â of a phenomenally given world. This attention to âstanding appearancesâ, which Kant identifies in optical illusions as the very essence of appearance [Schein], makes his discussion with Lambert interesting as part of an early history of pictorial technologies.
As Erich Adickes remarks in the 1913 edition of Kantâs handwritten Nachlass, published as volume XV of the Academy Edition, the existence of Kantâs Opponent-Rede was long known.2 Yet it was not until 1910 that Arthur Warda first published it in the AltpreuĂische Monatsschrift. The Latin text, though in places somewhat inscrutable, was swiftly translated into German and accompanied by a commentary by Bernhard Adolf Schmidt, published in Kant-Studien under the title, âEine bisher unbekannte lateinische Rede Kants ĂŒber SinnestĂ€uschung und poetische Fiktionâ [âA Previously Unknown Latin Speech by Kant on Sensory Illusion and Poetic Fictionâ] (Schmidt 1911, 5â21).3 It is to the latter publication that VorlĂ€nder refers in his first Kant book.
True to his word in this early work, VorlĂ€nder takes up the philosophical significance of Kantâs speech again in his later compendium, Immanuel Kant. Der Mann und das Werk â published twelve years later and at three times the length. Among Kantâs âmore ingeniously dashed-off than strictly systematic explorationsâ VorlĂ€nder calls special attention to:
[âŠ] the concept of playful illusion or semblance as a fundamental element of all poetry, the ideas of the magic of the senses and of the elevation of literature, the distinction between natural and poetical love (Petrarchâs sonnets to Laura), between the poet and the philosopher, the separation between the domains of poesy and logic, the conception of the task of the latter.
(1992, I, 394)
Despite the obvious relevance of these themes, VorlĂ€nderâs 1924 Kant book does not repeat his earlier claim that the speechâs âsignificance [is] not to be underestimatedâ. Instead, he clarifies that his aim is not to trace the gradual development of Kantâs aesthetic theory using the recently published Nachlass, but rather to portray Kant âalways in the first instance only as philosopherâ. With this declaration of intentions, however, VorlĂ€nder not only removes the speech from the center of philosophical concern, but simultaneously excludes aesthetic questions from the core domain of philosophy itself.
The interest in optical illusions
The concept of illusion Kant employs in his Opponenten-Rede is drawn from aesthetics and was used well into the 1780s to refer to misperceptions or sensory delusions that are accompanied by a consciousness of the non-reality of the represented object (for an extensive discussion, see Strube 1971; for an overview, see Strube 1976).
Over the course of the eighteenth century, the word âillusionâ, which simply meant âsensory delusionâ in common French parlance, was adapted by French aesthetic theorists such as AbbĂ© Dubos and Diderot and introduced into aesthetic discourse. It made its way into German aesthetics through authors such as Mendelssohn, Lessing, and Sulzer, as well as Kantâs friend and Kreutzfeldâs predecessor Johann Gotthelf Lindner. In 1757, Mendelssohn, for example, characterizes âaesthetic illusion [Illusion]â as an
[âŠ] imitation that has so much similarity to the original [Urbilde] that our senses can convince themselves, at least for a moment, of seeing the original itself.
(1972 [1757], 154)
If an imitation is to be âbeautifulâ, Mendelssohn continues, âthe higher powers of the soul, however, must be convinced that it is an imitation and not nature itselfâ (ibid., 154). In his 1771 Philosophische Schriften, Mendelssohn corrects himself in connection with Dubosâs description of the âaesthetic state [Zustand]â and admits that the soul allows itself to be carried along and deceived by art. âOnlyâ, he admits,
this magic lasts only as long as is necessary to give our concept of the object the appropriate fire and life. As soon as the relation to the object begins to become unpleasant, however, we remember thousands of obvious factors [revealing] that we are seeing a mere imitation before us.
(1971, 390)
Illusion, for Mendelssohn, is characterized by a twofold representational process. The soul represents the depicted object through the senses as an object. Illusion is, to that extent, sensory delusion. At the same time, however, the soul remains conscious (through its higher faculties) that it is dealing with a mere representation, a mere sensory illusion. In this manner, the soul assures itself of the supremacy of the understanding over the senses, which constitutes the genuinely educational effect of aesthetic illusion.
Mendelssohn stands squarely within contemporaneous consensus in speaking of illusion in connection with imitations on the âstage, on canvas, in marbleâ â i.e. in connection with theatre, painting, and sculpture (ibid.). Illusion unites those disciplines in which the assumption that genuine art consists in deceiving the senses has a long tradition. As early as Platoâs Republic, we find the claim that painters, as imitators, have the ability to deceive children and fools. If this was, for Plato, a reason to assert the inferiority of art, the argument had so reversed itself by the eighteenth century (with the popular reception of the story of Zeuxis and Parrhasius4) that, now, skill in figurative art could be measured by the deceptive genuineness of the imitations produced.
In addition to the visual arts, the production of sensory illusion played a central role in rhetoric. It was central to the theory of enthusiasm, according to which speakers could, through their animation, see the things they described as though they were really there before their eyes. The animation and inspiration of the speaker could, on this theory, communicate itself to the public through sympathy, so that the audience would forget where they were in order to allow themselves to be completely carried away by the speech. This state was termed âpathetic illusionâ and was considered legitimate when it was furnished with a moral-pedagogical function.5
The transference of the theory of enthusiasm onto the doctrine of aesthetic illusion has the consequence that illusion comes to be associated with the moral improvement of the deluded viewer and thereby morally legitimated.
This conception of aesthetic illusion as a morally legitimate delusion of the senses forms the basis on which Kant, in his speech against Kreutzfeld, distinguishes between illusion as permissible delusion and impermissible deceit. He introduces the concept of illusion in a general prefatory remark that precedes his critical commentary on Kreutzfeldâs discussion of the universal ground of fictional production. Kant thus makes clear from the outset how he himself thinks about the theme of fiction (AA 15.2:903ff.).
There is, Kant claims early on, âa kind of illusion [fallendi] that is clearly not disreputableâ (AA 15.2:906). It flatters the ear, stimulates the mind through an âillusory appearance [fictis rerum speciebus]â, and elevates it (AA 15.2:906). This sort of deception Kant terms âplayful appearanceâ. It eschews any âevil intentâ (AA 15.2:906). Moreover, the author of such illusion not only does not mean to incite error, he seeks to present âthe truth, clothed in the dress of appearance, which does not obscure its inner essence, but sets it adorned before [our] eyesâ (AA 15.2:906). Thus, the appearance does not deceive through ornamentation and adornment, but uses the perspicuity of the senses to allow âthe colorless image of truth, painted in sensible colors, to enter into appearanceâ (AA 15.2:907). Kant calls this play of appearances âillusion [illusio]â and distinguishes it from the âappearance that deceives [fallit]â, which he connects with the concept of deceit (fraude) (AA 15.2:907, 908). Illusion is not only permissible, it pleases âin high measureâ (AA 15.2:907); whereas deceptive illusion, once discovered, arouses resentment.
Up to this point, Kantâs remarks align with textbook versions of fine artsâ provisions for aesthetic illusion. He departs from the standard version, however, by abruptly introducing optical illusion [illusionibus opticis] as an example of illusion thus theorized. In contrast to the cheap conjuring tricks and deceptions of the entertainer, according to Kant, optical illusion is not meant to deceive its recipients. Entertainers are in the business of misrepresenting appearance as truth, and their arts retain their fascination only so long as the deceptive appearance is not seen through. The moment the viewer understands the appearance, they also understands they have been tricked. The result is simultaneous awe and âindignation at being won over by the slyness of the deceiverâ (AA 15.2:908).
In the case of optical illusions, by contrast, the viewer is protected from error since the appearance is readily seen through. The art here consists in keeping the mind in motion âfluctuating, as it were, at the borderline between error and truthâ (AA 15.2:907). In this way, the appearance endures even as the optical delusion is seen through. Illusion is thus distinguished by the fact that the conditions of the appearance can be seen through, as in the case of optical illusion, without the appearance ceasing to have effect. And just as suddenly as Kant introduced the concept of optical illusion, he continues by asserting the connectedness of optical appearance and the literary arts [Dichtung].
Kant expounds his understanding of optical illusion in Anthropology from a Pragmatic Point of View by means of three concrete examples. First, âthe perspectival drawing of the interior of a templeâ; second, the painting of the peripatetic school, of which it is said âthey appear to move when one looks at them a long timeâ; and third, âthe Amsterdam town hall painting of a staircase behind a half-opened door, that misleads visitors into trying to climb itâ (AA 7:150).
From his examples, it is clear that Kant is not thinking of a ânatural phenomenonâ when discussing optical illusion, but instead of the technique of perspective. But what is the connection between single-point perspective and literature [Dichtung]? And how is it that these arts, by employing optical illusion in ways that fool our senses, âwrest the prize from most other artsâ, as Kant claims in the Opponenten-Rede (AA 15.2:909)?