Hermann von Helmholtz

German physician Hermann L. F. von Helmholtz (1821–1894) studied medicine at the

“Royal Medical and Surgical Friedrich-Wilhelms Institute” in Berlin from 1838 to 1842 to become a surgeon serving in the Prussian army. After practising this profession in Berlin he devoted himself to academic work, which lead him later to professorships at several important universities, such as Königsberg, Bonn, Heidelberg and Berlin. The turning point in Helmholtz‖s academic career was his paper on the conservation of energy (Ueber die Erhaltung der Kraft), which he presented to the Physikalische Gesellschaft (“Physical Society”) in Berlin in 1847. Although Helmholtz was primarily a physiologist and a

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physicist, with Fechner and Wundt he is regarded first in importance in establishing experimental psychology.

After becoming associate professor at Königsberg (1849), Helmholtz began his investigations on the physiology of sensation. In 1851 he invented the ophthalmoscope and later the ophthalmometer to observe the physiology of the retina and mechanisms of vision (i.e., a necessary device to illuminate the retina and to measure the rates of nervous impulses). These investigations were later converted into the Handbuch der physiologischen Optik (1856). Further to its status as a classic in its field, it contains some groundbreaking remarks on sensation and perception that were also important for Helmholtz‖s contribution to aesthetics. The concept of “unconscious inference” (unbewusster Schluss) is not only an important part of Helmholtz‖s theory of perception but also highlights his firm belief in empiricism. Helmholtz introduced his theory of unconscious inference in his second volume of the Optik (1860) and gave a full exposition in the third volume in 1866.

Roughly put, what Helmholtz was arguing with the occurence of unconscious inference was that perception may contain many experiential data that are not immediately represented in the stimulus. These unconsciously determined phenomena in the process of perception accrue to it in accordance with its development in past experience. (Boring 1950: 308–309.)

According to Helmholtz, the three most essential definitions to unconscious inferences are that they are normally irresistible, formed by experience, and that their results assimilate conscious inferences and thus inductive. Helmholtz illustrated the irresistible aspect with the example of optical illusions, many of which are practically compulsory. By the experiental aspect, Helmholtz meant that unconscious inferences are actually at first conscious: by association and repetition they develop into unconscious inferences. It was natural for Helmholtz to make this kind of statement, since he held that in experience or perception there are no innate ideas, i.e., a priori knowledge. As discussed by Boring (ibid.

305–306), in opposition to Kant‖s philosophy, Helmholtz believed that the development of perceptions in experience was to a certain extent demonstrable. With the inductive aspect, Helmholtz claimed that similar to conscious inductive reasoning, the brain makes quick and automatic generalizations about perceptions. According to Helmholtz this demonstrated how sensation was prior to unconscious inference, unlike perception, which is dependent on it. To clarify this path of thought, Boring (ibid. 311) quotes a passage from Helmholtz:

Nothing in our sense-perceptions can be recognized as sensation which can be overcome in the perceptual image and converted into its opposite by factors that are demonstrably due to experience.

Perception (Perzeption, bare sensory pattern) is thus almost always supplemented and modified by an imaginal increment. The object of the perception is accordingly an aggregate of sensations, formed in experience and reconstructed or build up in “mental experimentation”, as Boring (ibid. 310–312) points out. In other words, “perception” is thus a mere subjective reconstruction of the objective world, which our sensory systems inaccurately transmit to us. This is a familiar pattern to semioticians acquainted with Peirce‖s triadic model of sign.

Helmholtz‖s conception of perception and sensation involves the idea of the different degrees of consciousness. In becoming conscious of a sensation, two different kinds or

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grades should be distinguished: in the lower grade of consciousness the influence of the sensation in question makes itself felt only in the conceptions we form of external things and processes, and assists in determining them. According to Helmholtz this is what Leibniz calls perception.²⁸⁷ On the second, or higher grade of awareness, the sensation is immediately distinguished as an existing part of the sum of the sensations excited in us.

According to Helmholtz, this is what Leibniz meant with apperception.²⁸⁸ (Helmholtz 1954: 62; discussion on the partials of the compound tones.)

The culmination in Helmholtz‖s career was his research on physiological acoustics that resulted in the publication of the famous Die Lehre von den Tonempfindungen als physiologische Grundlage für die Theorie der Musik (“On the Sensations of Tone as a physiological Basis for the Theory of Music”) in 1863. At this time, Helmholtz was working as a professor of physiology in Heidelberg (from 1858) after a short period spent in Bonn. As made explicit by its title, the focus of the book is not in acoustics, but in the physical physiology of aural sensation. In his introductory words, Helmholtz states that his book seeks to combine the margins of different sciences, namely, physical and physiological acoustics, and musicology and aesthetics.²⁸⁹ In its field Die Lehre von den Tonempfindungen has acquired a similar status as Helmholtz‖s Handbuch der physiologischen Optik. According to Helmholtz the first part of the Tonempfindungen is essentially concerned about physical and physiological contents. The anatomy of the ear, including Helmholtz‖s resonance theory of hearing,²⁹⁰ is discussed here. The second part investigates the problems of musical elements, such as composite tones, harmony, consonance and dissonance. As Helmholtz (ibid. 8) remarks, no aesthetic questions are being discussed in these parts of the book. Finally, the third part focuses on the construction of tonality, scales and diversity of style, involving also closely related areas in aesthetics. Commenting on his physiological approach and the challenges of musical aesthetics, Helmholtz (ibid.

371) closes his work by stating:

In all these fields [the aesthetics of music, the theory of rhythm, forms of composition, and means of musical expression] the properties of sensual perception would of course have an influence at times, but only in a very subordinate degree. The real difficulty would lie in the development of the psychical motives which here assert themselves. Certainly this is the point where the more interesting part of musical esthetics begins, the aim being to explain the

287 Dabei zeigt es sich denn, dass wir für das Bewusstwerden einer Empfindung zwei verschiedene Arten oder Grade unterscheiden müssen. Der niedere Grad des Bewusstwerdens ist derjenige, bei welchem der Einfluss der betreffenden Empfindung sich nur in der von uns gebildeten Vorstellung von den äusseren Dingen und Vorgängen geltend macht und diese bestimmen hilft. Wir wollen in diesem Falle mit Leibniz den Ausdruck brauchen, dass der betreffende Empfindungseindruck p e r z i pi e r t sei. (Helmholtz 1913: 107.)

288 Der zweite, höhere Grad des Bewusstwerdens ist der, wo wir die betreffende Empfindung unmittelbar als einen vorhandenen Teil der zurzeit in uns erregte Summe von Empfindungen unterscheiden. Eine solche Empfindung wollen wir als wahrgenommen (a p p e r z i p i e r t nach Leibniz) bezeichnen. (Helmholtz 1913:

107.)

289 Das vorliegende Buch sucht die Grenzgebiete von Wissenschaften zu vereinigen, welche, obgleich durch viele natürliche Beziehungen aufeinander hingewiesen, bisher doch ziemlich getrennt nebeneinander gestanden haben, die Grenzgebiete nämlich einerseits der physikalischen und physiologischen Akustik, andererseits der Musikwissenschaft und Ästhetik. (Helmholtz 1913: 1.)

290 By the invention and use of specific resonators (which amplify the overtones of composite tones), Helmholtz was able to measure the speed of nerve impulses and to explain how the inner ear, its cochlea and basilar membrane work.

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wonders of great works of art, and to learn the utterances and actions of the various affections of the mind. But, however alluring such an aim may be, I prefer leaving others to carry out such investigations, in which I should feel myself too much of an amateur, while I myself remain on the safe ground of natural philosophy, in which I am at home.

Helmholtz was among the first to find out that unlike pure tones, composite tones and their timbres (for example of different instruments or speech) are formed and perceived on the basis of their overtones (the literal translation of the German Oberton), so-called upperpartial tones. At Helmholtz‖s time, pure tones (i.e., sounds without upper partials) were produced for acoustic investigation by tuning-forks. According to Helmholtz, harmony, dissonance and consonance are based on the relations of these upperpartials.

Thus, the ear is understood as a frequency analyzer. According to Helmholtz, a totally different matter is what harmony or dissonance is considered to be in different times and cultures.

Helmholtz claimed that the research on the physiology of hearing and acoustics should provide a basis for the theory and aesthetics of music. As distinct from the other arts, Helmholtz stated that music has a more immediate connection with pure sensation.

Consequently, the theory of the sensations of hearing was to play a much more important part in musical aesthetics, than, for example, the theory of chiaroscuro or of perspective in painting.²⁹¹ As Helmholtz argued, music alone finds an infinitely rich but totally shapeless plastic material in the tones of the human voice and artificial musical instruments, resulting in the fact that there is a greater and more absolute freedom in the use of the material for music than for any other of the arts. In music, no perfect representation of nature is aimed at; tones and the sensations of tone exist for themselves alone, and produce their effects independently of anything behind them.²⁹² (Helmholtz 1954: 3.) Furthermore, in the third part of the book, Helmholtz claims that just as people with differently directed tastes could erect extremely different kinds of buildings with the same stones, the history of music similarly shows us that the same properties of the human ear could serve as the foundation of very different musical systems. This led Helmholtz to the statement that the construction of our system of scales, keys, chords, in short of all that is usually comprehended in a treatise on Thorough Bass, is the work of artistic invention, and hence must be subject to laws of artistic beauty. (Helmholtz 1913: 587–588; Helmholtz 1954:

366.)

In the light of the arguments mentioned earlier, it is obvious that Helmholtz was inclined to link his emphasis on physiological sensation as the foundation for music theory with Hanslick‖s anti-representational aesthetics. He praised Hanslick for “triumphantly attacking the false standpoint of exaggerated sentimentality, from which it was fashionable to theorise on music, and referring the critic to the simple elements of melodic

291 In diesem Sinne ist es klar, dass die Musik eine unmittelbarere Verbindung mit der sinnlichen Empfindung hat, als irgend eine der anderen Künste; und daraus folgt denn, dass die Lehre von den Gehörempfindungen berufen sein wird, in der musikalischen Ästhetik eine viel wesentlichere Rolle zu spielen, als etwa die Lehre von der Beleuchtung oder der Perspektive in der Malerei (Helmholtz 1913: 4).

292 In der Musik dagegen wird gar keine Naturwahrheit erstrebt, die Töne und Tonempfindungen sind ganz allein ihrer selbst wegen da und wirken ganz unabhängig von ihrer Beziehung zu irgendeinem äusseren Gegenstande (Helmholtz 1913: 4).

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movement”²⁹³ (Helmholtz 1954: 2). Although Helmholtz agreed that music can represent (only) frames of mind and mental states (instead of feelings and situations, cf. ibid. 251), sensuous pleasure and aesthetic beauty should be kept strictly apart. The theory of music and the foundation of its structure should ultimately be based on scientific investigation, i.e., on physiological acoustics.