Exclusive 3:16 interview with Hermann Helmholtz

Hermann von Helmholtz (1821–1894) participated in two of the most significant developments in physics and in the philosophy of science in the 19th century: the proof that Euclidean geometry does not describe the only possible visualizable and physical space, and the shift from physics based on actions between particles at a distance to the field theory. Helmholtz achieved a staggering number of scientific results, including the formulation of energy conservation, the vortex equations for fluid dynamics, the notion of free energy in thermodynamics, and the invention of the ophthalmoscope. His constant interest in the epistemology of science guarantees his enduring significance for philosophy. (Lydia Patton) Here he discusses his theories of perception and music.

3:16: What made you become a philosopher? 

Hermann Helmholtz: The problems which that earlier period considered fundamental to all science were those of the theory of knowledge: What is true in our sense perceptions and thought? and In what way do our ideas correspond to reality? Philosophy and the natural sciences attack these questions from opposite directions, but they are the common problems of both. 

3:16: So your approach is multi-disciplinary – you see philosophy and science working side by side? 

HH: Of course. Philosophy, which is concerned with the mental aspect, endeavours to separate out whatever in our knowledge and ideas is due to the effects of the material world, in order to determine the nature of pure mental activity. The natural sciences, on the other hand, seek to separate out definitions, systems of symbols, patterns of representation, and hypotheses, in order to study the remainder, which pertains to the world of reality whose laws they seek, in a pure form. Both try to achieve the same separation, though each is interested in a different part of the divided field. 

3:16: And this is partly because neither philosophers nor scientists can ignore questions of epistemology that confront them? 

HH: That’s right Richard. The natural scientist no more than the philosopher can ignore epistemological questions when he is dealing with sense perception or when he is concerned with the fundamental principles of geometry, mechanics, or physics. Since my work has entered many times into both the region of science and the region of philosophy, I should like to attempt to survey what has been done from the side of the natural sciences to answer the questions which have just been stated. The laws of thought, after all, are the same for the scientist as for the philosopher. 

3:16: So both philosophy and natural sciences are to you really sciences. Can you say what they’re trying to solve? 

HH: The problem of the sciences is, in the first place, to seek the laws by which the particular processes of nature may be referred to, and deduced from, general rules. These rules—for example, the law of the reflection and refraction of light, the law of Mariotte and Gay-Lussac regarding the volumes of gases—are evidently nothing more than general ideas by which the various phenomena which belong to them are connected together. The finding out of these is the office of the experimental portion of our science. The theoretic portion seeks, on the contrary, to evolve the unknown causes of the processes from the visible actions which they present; it seeks to comprehend these processes according to the laws of causality 

3:16: Kant is someone you find a useful starting point in trying to do this don’t you? 

HH: Kant and Locke Richard. Kant expounded a theory of that which, in cognition, is prior or antecedent to all experience; that is, he developed a theory of what he called the transcendental forms of intuition and thought. These are forms into which the content of our sensory experience must necessarily be fitted if it is to be transformed into ideas. As to the qualities of sensations themselves, Locke had earlier pointed out the role which our bodily and mental structure or organisation plays in determining the way things appear to us. Along this latter line, investigations of the physiology of the senses, in particular those which Johannes Müller carried out and formulated in the law of the specific energies of the senses, have brought (one can almost say, to a completely unanticipated degree) the fullest confirmation. Further, these investigations have established the nature of - and in a very decisive manner have clarified the significance of - the antecedently given subjective forms of intuition. 

3:16: So Kant’s ‘transcendental forms’ are Kant’s way of building a mental model which explains how we think. The input of sensations is crucial to this isn’t it– and you make two distinctions regarding them don’t you as you try and categorise the various types of sensation we encounter. 

HH: Yes. The most fundamental is that among sensations which belong to different senses, such as the differences among blue, warm, sweet, and high- pitched. I refer to these as differences in the modality of the sensations. They are so fundamental as to exclude any possible transition from one to another and any relationship of greater or less similarity. For example, one cannot ask whether sweet is more like red or more like blue. The second distinction, which is less fundamental, is that among the various sensations of the same sense. I have referred to these as differences in quality.   

3:16: And Fichte has some insights here doesn’t he?    

HH: Yes. Fichte thought of all the qualities of a single sense as constituting a circle of quality; what I have called differences of modality, he designated differences between circles of quality. Transitions and comparisons are possible only within each circle; we can cross over from blue through violet and carmine to scarlet, for example, and we can say that yellow is more like orange than like blue. 

3:16: So what’s the role of sensations in your understanding of how we perceive the world? 

HH: Well, physiological studies now teach that the more fundamental differences are completely independent of the kind of external agent by which the sensations are excited. They are determined solely and exclusively by the nerves of sense which receive the excitations. Excitations of the optic nerves produce only sensations of light, whether the nerves are excited by objective light (that is, by the vibrations in the ether), by electric currents conducted through the eye, by a blow on the eyeball, or by a strain in the nerve trunk during the eyes' rapid movements in vision. The sensations which result from the latter processes are so similar to those caused by objective light that for a long time men believed it was possible to produce light in the eye itself. It was Johannes Müller who showed that internal production of light does not take place and that the sensation of light exists only when the optic nerve is excited. 

3:16: So how can we tell if there’s anything like what we think there is causing these sensory inputs? It seems like we can’t know if we are perceiving the world – maybe all we’re experiencing is the jiggling of nerve endings. 

HH: Basically Richard our sensations are simply effects which are produced in our organs by objective causes; precisely how these effects manifest themselves depends principally and in essence upon the type of apparatus that reacts to the objective causes. You ask what information, then, can the qualities of such sensations give us about the characteristics of the external causes and influences which produce them? Only this: our sensations are signs, not images, of such characteristics. 

3:16: So it’s a mistake to think we’re getting direct access to the external causes and influences that produce our sensations? What we’re getting are signs built from the sensory apparatus we have. This is very Kantian. 

HH: Exactly. Our sensations are simply effects which are produced in our organs by objective causes; precisely how these effects manifest themselves depends principally and in essence upon the type of apparatus that reacts to the objective causes. So when you ask what information, then, can the qualities of such sensations give us about the characteristics of the external causes and influences which produce them I say only this: our sensations are signs, not images, of such characteristics. One expects an image to be similar in some respect to the object of which it is an image; in a statue one expects similarity of form, in a drawing similarity of perspective, in a painting similarity of colour. A sign, however, need not be similar in any way to that of which it is a sign. The sole relationship between them is that the same object, appearing under the same conditions, must evoke the same sign; thus different signs always signify different causes or influences. 

3:16: This is not what our folk belief about perception tell us is it? We tend to think we look out and we see the tables, people, stars before us. But you’re saying these things are inferences we build out of our mental mechanisms, constructing intelligible signs for us about the world. But they need have no similarity to the actual world causing these signs. Doesn’t this mean we’re kind of hallucinating reality? It’s a subjective dream space we’re creating, or a David Chalmers like virtual reality space? 

HH: Steady now Richard, let’s not get giddy! Let’s step back a little. To popular opinion, which accepts on faith and trust the complete veridicality of the images which our senses apparently furnish of external objects, this relationship may seem very insignificant. In truth it is not, for with it something of the greatest importance can be accomplished: we can discover the lawful regularities in the processes of the external world. And natural laws assert that from initial conditions which are the same in some specific way, there always follow consequences which are the same in some other specific way. If the same kinds of things in the world of experience are indicated by the same signs, then the lawful succession of equal effects from equal causes will be related to a similar regular succession in the realm of our sensations. If, for example, some kind of berry in ripening forms a red pigment and sugar at the same time, we shall always find a red colour and a sweet taste together in our sensations of berries of this kind. 

Thus, even if in their qualities our sensations are only signs whose specific nature depends completely upon our make-up or organisation, they are not to be discarded as empty appearances. They are still signs of something - something existing or something taking place - and given them we can determine the laws of these objects or these events. And that is something of the greatest importance! 

3:16: And Kant makes this point too doesn’t he? 

HH: Kant went further Richard. He claimed that, not only the qualities of sense experience, but also space and time are determined by the nature of our faculty of intuition, since we cannot perceive anything in the external world which does not occur at some time and in some place and since temporal location is also a characteristic of all subjective experience. Kant therefore called time the a priori and necessary transcendental form of the inner, and space the corresponding form of the outer, intuition. Further, Kant considered that spatial characteristics belong no more to the world of reality (the dinge an sich) than the colours we see belong to external objects. On the contrary, according to him, space is carried to objects by our eyes. 

3:16: Does science back him up? 

HH: Even in this claim, scientific opinion can go along with Kant up to a certain point. Let us consider whether any sensible marks are present in ordinary, immediate experience to which all perception of objects in space can be related. Indeed, we find such marks in connection with the fact that our body's movement sets us in varying spatial relations to the objects we perceive, so that the impressions which these objects make upon us change as we move. The impulse to move, which we initiate through the innervation of our motor nerves, is immediately perceptible. We feel that we are doing something when we initiate such an impulse. We do not know directly, of course, all that occurs; it is only through the science of physiology that we learn how we set the motor nerves in an excited condition, how these excitations are conducted to the muscles, and how the muscles in turn contract and move the limbs. We are aware, however, without any scientific study, of the perceptible effects which follow each of the various innervations we initiate. 

3:16: You conduct a thought experiment to show this – you imagine someone without any experiences at all. Can you take us through this and what it shows? 

HH: In order to begin without any intuition of space, we must assume that such an individual no longer recognises the effects of his own innervations, except to the extent that he has now learned how, by means of his memory of a first innervation or by the execution of a second one contrary to the first, to return to the state out of which he originally moved. Since this mutual self-annulment of different innervations is completely independent of what is actually perceived, the individual can discover how to initiate innervations without any prior knowledge of the external world. Let us assume that the man at first finds himself to be just one object in a region of stationary objects. As long as he initiates no motor impulses, his sensations will remain unchanged. However, if he makes some movement (if he moves his eyes or his hands, for example, or moves forward), his sensations will change. And if he returns (in memory or by another movement) to his initial state, all his sensations will again be the same as they were earlier. 

If we call the entire group of sensation aggregates which can potentially be brought to consciousness during a certain period of time by a specific, limited group of volitions the temporary presentabilia in contrast to the present, that is, the sensation aggregate within this group which is the object of immediate awareness - then our hypothetical individual is limited at any one time to a specific circle of presentabilia, out of which, however, he can make any aggregate present at any given moment by executing the proper movement. Every individual member of this group of presentabilia, therefore, appears to him to exist at every moment of the period of time, regardless of his immediate present, for he has been able to observe any of them at any moment he wished to do so. 

This conclusion - that he could have observed them at any other moment of the period if he had wished - should be regarded as a kind of inductive inference, since from any moment a successful inference can easily be made to any other moment of the given period of time. 

3:16: So this helps present us with your idea that we are inference machines out of which we can infer space and time from the kind of world we model from our mental apparatus? And it’s not just Kant here but Fichte who you draw on? 

HH: Indeed Richard. In this way the idea of the simultaneous and continuous existence of a group of different but adjacent objects may be attained. Adjacent is a term with spatial connotations, but it is legitimate to use it here, since we have used spatial to define those relations which can be changed by volition. Moreover, we need not restrict the term adjacent so that it refers only to material objects. For example, it can legitimately be said that "to the right it is bright, to the left dark," and "forward there is opposition, behind there is nothing," in the case where "right" and "left" are only names for specific movements of the eyes and "forward" and "behind" for specific movements of the hands. At other times the circles of presentabilia related to this same group of volitions are different. In this way circles of presentabilia, along with their individual members, come to be something given to us, that is, they come to be objects. Those changes which we are able to bring about or put an end to by familiar acts of volition come to be separated from those which do not result from and cannot be set aside by such acts. This last statement is negative: in Fichte's quite appropriate terminology, the Non-Ego forces the recognition that it is distinct from the Ego. 

3:16: So this is an early version of a Markov blanket, of the absolutely necessary distinction we need to have anything by separating whatever a thing is from everything else. So you, Fichte and Kant are running ideas that are very important to Karl Friston and Andy Clark and their ideas of the predictive brain and free energy principles? 

HH: Never heard of them Richard – give me references and I’ll look them up after this, they sound important - but the Markov Blanket notion which renders a set of states, internal and external states, conditionally independent of one another,  seems spot on. 

But getting back to what I was saying, when we inquire into the empirical conditions under which our intuition of space is formed, we must concentrate in particular upon the sense of touch, for the blind can form complete intuitions of space without the aid of vision. Even if space turns out to be less rich in objects for them than for people with vision, it seems highly improbable that the foundation of the intuition of space is completely different for the two classes of people. If, in the dark or with our eyes closed, we try to perceive only by touch, we are definitely able to feel the shapes of the objects lying around us, and we can determine them with accuracy and certainty. Moreover, we are able to do this with just one finger or even with a pencil held in the hand the way a surgeon holds a probe. Ordinarily, of course, if we want to find our way about in the dark we touch large objects with five or ten fingertips simultaneously. In this way we get from five to ten times as much information in a given period of time as we do with one finger. 

3:16: So we build or infer a three dimensional space out of this process? 

HH: Three dimensions are sufficient for all our experience, since a closed surface completely divides space as we know it. Moreover, substances in a gaseous or fluid state, which are not dependent at all on the nature of man's mental faculties, cannot escape from a completely closed surface. And, just as a continuous line can enclose only a surface and not a space - that is, a spatial form of two and not of three dimensions - so a surface can enclose only a space of three and not of four dimensions. So yes Richard, it is thus that our knowledge of the spatial arrangement of objects is attained. Judgments concerning their size result from observations of the congruence of our hand with parts or points of an object's surface, or from the congruence of the retina with parts or points of the retinal image. 

3:16: How do we attain the qualities of our sensations of these objects in space? 

HH: The perceived spatial ordering of things originates in the sequences in which the qualities of sensations are presented by our moving sense organs: the objects in the space around us appear to possess the qualities of our sensations. They appear to be red or green, cold or warm, to have an odour or a taste, and so on. Yet these qualities of sensations belong only to our nervous system and do not extend at all into the space around us. Even when we know this, however, the illusion does not cease, for it is the primary and fundamental truth. The illusion is quite simply the sensations which are given to us in spatial order to begin with. You can see how the most fundamental properties of our spatial intuition can be obtained in this way. 

3:16: So we’re construction them. They’re not really out there? This is again Kant’s point isn’t it? 

HH: Yes. An intuition is taken to be something which is simply given, something which occurs without reflection or effort, something which above all cannot be reduced to other mental processes. This popular interpretation, at least insofar as the intuition of space is concerned, is due in part to certain theorists in physiological optics and in part to a strict adherence to the philosophy of Kant. As is well known, Kant taught, not only that the general form of the intuition of space is given transcendentally, but also that this form possesses, originally and prior to a possible experience, certain more specific characteristics which are commonly given expression in the axioms of geometry. These axioms may be reduced to the following propositions: Between two points there is only one possible shortest line. We call such a line straight. A plane is determined by three points. A plane is a surface which contains completely any straight line between any two of its points. Through any point there is only one possible line parallel to a given straight line. Two straight lines are parallel if they lie in the same plane and do not intersect upon any finite extension. 

3:16: Kant took these to be absolutely necessary axioms of geometry but we know now thanks to advances in physics they’re not don’t we? 

HH: Kant used the alleged fact that these propositions of geometry appear to us necessarily true, along with the fact that we cannot imagine or represent to ourselves any irregularities in spatial relations, as direct proof that the axioms must be given prior to all experience. It follows that the conception of space contained in them or implied by them must also constitute a transcendental form of intuition independent of all experience. I would like to emphasise here, in connection with the controversies which have sprung up during the past few years as to whether the axioms of geometry are transcendental or empirical propositions, that this question is absolutely different from the one mentioned earlier, namely, whether space in general is a transcendental form of intuition or not. 

3:16: Can you explain what you mean? 

HH: Our eyes see everything in the field of vision as a number of colored plane surfaces. That is their form of intuition. However, the particular colours that appear at any one time, the relationships among them, and the order in which they appear are the effects of external causes and are not determined by any law of our organisation. Equally, the fact that space is a form of intuition implies just as little concerning the facts which are expressed by the axioms. If these axioms are not empirical propositions but rather pertain to a necessary form of intuition, this is a further and quite specific characteristic of the general form, and the same reasoning which was used to establish that the general form of intuition of space is transcendental is not necessarily sufficient to establish that the axioms also have a transcendental origin. In his assertion that it is impossible to conceive of spatial relations which contradict the axioms of geometry, as well as in his general interpretation of intuition as a simple, irreducible mental process, Kant was influenced by the mathematics and the physiology of the senses of his time. 

3:16: Ok, so how do we think about something that we have never seen before? 

HH: To do that it is necessary to know how to imagine in detail the series of sense impressions which, in accordance with well-known laws, would be experienced if the thing in question - and any changes in it - were actually perceived by any of the sense organs from all possible positions. Further, these impressions must be such that all possible interpretations of them except one can be eliminated. If these series of sense impressions can be specified completely and uniquely in this way, then in my opinion one must admit that the object clearly is conceivable. 

3:16: So our minds draw on analytic geometry, on models of things we have in us? 

HH: Since by hypothesis the object has never been observed before, no previous experience can come to our aid and guide our imagination to the required series of impressions. Such guidance can be provided only by the concepts of the objects and relationships to be represented. Such concepts are first developed analytically as much as is necessary for the investigation at hand. Indeed, the concepts of spatial forms to which nothing in ordinary experience corresponds can be developed with certainty only by the use of analytic geometry. 

3:16: So this seems to be a different way of knowing and perceiving than the means by which input is immediately matched and shaped by our internal model? It doesn’t seem as instantaneous as reacting to an external stimulus. It seems slower, so are the inferences drawn in this way less real to us? 

HH: There is considerable disagreement on this issue. But for a demonstration of conceivability I require only that, for every means of observation, the corresponding sense impressions be sketched out clearly and unambiguously, if necessary with the aid of scientific knowledge of the laws of these methods of observation. To anyone who knows these laws, the objects or relationships to be represented seem almost real. Indeed, the task of representing the various spatial relationships of meta-mathematical spaces requires training in the understanding of analytical methods, perspective constructions, and optical phenomena. 

3:16: But this doesn’t seem like the older conception of how intuitions form our experiences. 

HH: You’re right. This goes counter to the older conception of intuition, according to which only those things whose ideas come instantly - that is, without reflection and effort - to consciousness along with the sense impressions are to be regarded as given through intuition. It is true that our attempts to represent meta-mathematical spaces do not have the effortlessness, speed, or immediate clarity of our perceptions of, say, the shape of a room which we enter for the first time or of the arrangement and shape of the objects in it, the materials out of which they are made, and many other things. If this kind of immediate evidence is really a fundamental, necessary characteristic of an intuition, we cannot rightly claim the conceivability of meta-mathematical spaces. 

3:16: But you don’t think this notion of immediate evidence is fundamental do you? 

HH: I don’t Richard. There are a large number of experiences which show that we can develop speed and certainty in forming specific ideas after receiving specific sense impressions, even in cases where there are no natural connections between the ideas and the impressions. One of the most striking examples of this is learning a native language. Words are arbitrarily or accidentally selected signs, and in every language they are different. Knowledge of these signs is not inherited; to a German child who has been raised among French-speaking people and who has never heard German spoken, it is a foreign language. A child learns the meanings of words and sentences only by examples of their use; and before he understands the language, it is impossible to make intelligible to him the fact that the sounds he hears are signs which have meaning. 

Finally, however, after he has grown up, he understands these words and sentences without reflection, without effort, and without knowing when, where, or through what examples he learned them. He understands the most subtle shifts in their meaning, shifts which are often so subtle that any attempt to define them logically could be carried out only with difficulty. 

3:16: You think art also helps illustrate your point. 

HH: Art, most clearly poetry and the plastic arts, is based directly upon such experiences. The highest kind of perception, that which we find in the artist's vision, is an example of this same basic kind of understanding, in this case the understanding of new aspects of man and nature. Among the traces which frequently repeated perceptions leave behind in the memory, the ones conforming to law and repeated with the greatest regularity are strengthened, while those which vary accidentally are obliterated. In a receptive, attentive observer, intuitive images of the characteristic aspects of the things that interest him come to exist; afterward he knows no more about how these images arose than a child knows about the examples from which he learned the meanings of words. That an artist has beheld the truth follows from the fact that we too are seized with the conviction of truth when he leads us away from currents of accidentally related qualities. An artist is superior to us in that he knows how to find the truth amid all the confusion and chance events of daily experience. 

3:16: What you’re talking about here is what you once called the process of 'unconscious inference.' This is a crucial aspect of your theory of perception and thought isn’t it? 

HH: It is Richard. I called the connections of ideas which take place in these processes  unconscious inferences. These inferences are unconscious insofar as their major premise is not necessarily expressed in the form of a proposition; it is formed from a series of experiences whose individual members have entered consciousness only in the form of sense impressions which have long since disappeared from memory. Some fresh sense impression forms the minor premise, to which the rule impressed upon us by previous observations is applied. 

3:16: You seem to have backed off from using the phrase ‘unconscious inference’. Have you changed your mind on this? 

HH: Not at all Richard. I have refrained from using the phrase unconscious inference in order to avoid confusion with what seems to me a completely obscure and unjustified idea which Schopenhauer and his followers have designated by the same name. Obviously we are concerned here with the elementary processes which are the real basis of all thought, even though they lack the critical certainty and refinement to be found in the scientific formation of concepts and in the individual steps of scientific inferences. 

3:16: Ok. Now using your theory we can see that Kant’s claim that the axioms of geometry as transcendental is a mistake can’t we? 

HH: Yes. Any lack of facility in developing ideas of meta-mathematical spatial relations because of insufficient experience cannot be used validly as an argument against their conceivability. 

3:16: So contra Kant, you show that spatial relations are conceivable. 

HH: Yes. Kant's proof of the transcendental nature of the geometrical axioms is untenable. Indeed, investigation of the facts of experience shows that the axioms of geometry, taken in the only sense in which they can be applied to the external world, are subject to proof or disproof by experience. 

3:16: Memory plays a role in determining what we perceive doesn’t it? Your theory proposes that inferences drawn from previous experiences actually creates what we perceive doesn’t it? 

HH: Yes indeed, the memory traces of previous experience play an even more extensive and influential role in our visual observations. An observer who is not completely inexperienced receives without moving his eyes (this condition can be realised experimentally by using the momentary illumination of an electric discharge or by carefully and deliberately staring) images of the objects in front of him which are quite rich in content. We can easily confirm with our own eyes, however, that these images are much richer and especially much more precise if the gaze is allowed to move about the field of vision, in this way making use of the kind of spatial observations which I have previously described as the most fundamental. Indeed, we are so used to letting our eyes wander over the objects we are looking at that considerable practice is required before we succeed in making them - for purposes of research in physiological optics - fix on a point without wandering. 

3:16: Not everyone accepts this do they? 

HH: No. To a great many physiologists, however, whose point of view we shall call nativistic, in contrast to the empirical position which I have sought to defend, the idea that knowledge of the field of vision is acquired is unacceptable. It is unacceptable to them because they have not made clear to themselves what even the example of learning a language shows so clearly, namely, how much can be explained in terms of the accumulation of memory impressions. Because of this lack of appreciation of the power of memory, a number of different attempts have been made to account for at least part of visual perception through innate mechanisms by means of which specific sensory impressions supposedly induce specific innate spatial ideas. 

In early work I tried to show that all hypotheses of this kind which had been formulated were insufficient, since cases were always being discovered in which our visual perceptions are more precisely in agreement with reality than is stated in these hypotheses. With each of them we are forced to the additional assumption that ultimately experience acquired during movement may very well prevail over the hypothetical inborn intuition and thus accomplish in opposition to it what, according to the empirical hypothesis, it would have accomplished without such a hindrance. 

3:16: So these nativist approaches don’t really explain anything? 

HH: Spot on Richard! Nativistic hypotheses concerning knowledge of the field of vision explain nothing. 

3:16: You have three reasons why you think they fail haven’t you. Can you summarise these for us? 

HH: Sure. In the first place, they only acknowledge the existence of the facts to be explained, while refusing to refer these facts to well-confirmed mental processes which even they must rely on in certain cases. In the second place, the assumption common to all nativistic theories - that ready-made ideas of objects can be produced by means of organic mechanisms - appears much more rash and questionable than the assumption of the empirical theory that the non-cognitive materials of experience exist as a result of external influences and that all ideas are formed out of these materials according to the laws of thought. 

In the third place, the nativistic assumptions are unnecessary. The single objection that can be raised against the empirical theory concerns the sureness of the movements of many newborn or newly hatched animals. The smaller the mental endowment of these animals, the sooner they learn how to do all that they are capable of doing. The narrower the path on which their thoughts must travel, the easier they find their way. The newborn human child, on the other hand, is at first awkward in vision; it requires several days to learn to judge by its visual images the direction in which to turn its head in order to reach its mother's breast. 

3:16: So as inference machines right from the start our behaviour isn’t based on just experiences? 

HH: That’s right. The behaviour of young animals is, in general, quite independent of individual experience. Whatever these instincts are which guide them - whether they are the direct hereditary transmission of their parents' ideas, whether they have to do only with pleasure and pain, or whether they are motor impulses related to certain aggregates of experience - we do not know. In the case of human beings the last phenomenon is becoming increasingly well understood. Careful and critically employed investigations are most urgently needed on this whole subject. 

3:16: Isn’t there anything of value in the nativist approach? 

HH: What the nativistic hypotheses assume can at best have only a certain pedagogical value; that is, they may facilitate the initial understanding of uniform, lawful relations. And the empirical position is, to be sure, in agreement with the nativistic on a number of points - for example, that local signs of adjacent places on the retina are more similar than those farther apart and that the corresponding points on the two retina are more similar than those that do not correspond. For our present purposes, however, it is sufficient to know that complete spatial intuition can be achieved by the blind and that for people with vision, even if the nativistic hypotheses should prove partially correct, the final and most exact determinations of spatial relations are obtained through observations made while moving in various ways. 

3:16: Now let’s get back to your theory and one of the things that you emphasise is the intimate link between perception and actions in our inferences. Behaviours are mental. 

HH: The volition for a specific movement is a psychic act, and the perceptible change in sensation which results from it is also a psychic event. is it possible for the first to bring about the second by some purely mental process? It is certainly not absolutely impossible. Whenever we dream, something similar to this takes place. While dreaming we believe that we are executing some movement, and then we dream further that the natural results of this movement occur. 

We dream that we climb into a boat, shove it off from shore, guide it over the water, watch the surrounding objects shift position, and so on. In cases like this it seems to the dreamer that he sees the consequences of his actions and that the perceptions in the dream are brought about by means of purely Psychical processes. Who can say how long and how finely spun, how richly elaborated, such dreams may be! If everything in dreams were to occur in ultimate accordance with the laws of nature, there would be no distinction between dreaming and waking, except that the person who is awake may break off the series of impressions he is experiencing. 

3:16: This really does seem like you’re saying everything we think and do could be a dream, a kind of organised hallucination, or virtual reality at least? 

HH: I do not see how a system of even the most extreme subjective idealism, even one which treats life as a dream, can be refuted. One can show it to be as improbable, as unsatisfactory as possible (in this connection I concur with the severest expressions of condemnation), but it can be developed in a logically consistent manner, and it seems to me important to keep this in mind. How ingeniously Calderon carried out this theme in Life Is a Dream is well known. 

3:16: And again,Fichte’s insights seem important here for you? 

HH: Fichte also believed and taught that the Ego constructs the Non-Ego, that is, the world of phenomena, which it requires for the development of its Psychical activities. His idealism is to be distinguished from the one mentioned above, however, by the fact that he considered other individuals not to be dream images but, on the basis of moral laws, to be other Egos with equal reality. Since the images by which all these Egos represent the Non-Ego must be in agreement, he considered all the individual Egos to be part of or emanations from an Absolute Ego. The world in which they find themselves is the conceptual world which the World Spirit constructs. From this a conception of reality results similar to that of Hegel. 

3:16: Nevertheless it seems more intuitive to be a realist despite your theory. Where does this attraction to a realist hypothesis come from if its not right? 

HH: Realism accepts the evidence of ordinary personal experience, according to which the changes in perception which result from an act have more than a mere psychical connection with the antecedent volition. It accepts what seems to be established by our daily perception, that is, that the material world about us exists independently of our ideas. Undoubtedly the realistic hypothesis is the simplest that can be formulated. It is based upon and confirmed by an extraordinarily large number of cases. It is sharply defined in all specific instances and is therefore unusually useful and fruitful as a foundation for behaviour. 

3:16: So even if we’re Idealists the realist position is useful? 

HH: Even if we take the idealistic position, we can hardly talk about the lawful regularity of our sensations other than by saying: "Perceptions occur as if the things of the material world referred to in the realistic hypothesis actually did exist." We cannot eliminate the "as if" construction completely, however, for we cannot consider the realistic interpretation to be more than an exceedingly useful and practical hypothesis. We cannot assert that it is necessarily true, for opposed to it there is always the possibility of other irrefutable idealistic hypotheses. 

3:16: And this goes back to your contention that our inferences are not constrained by the evidence and causes? In this way you think both idealists and realists are inferring metaphysical positions don’t you? 

HH: Richard, it is always well to keep this in mind in order not to infer from the facts more than can rightly be inferred from them. The various idealistic and realistic interpretations are metaphysical hypotheses which, as long as they are recognised as such, are scientifically completely justified. 

3:16: But isn’t this dangerous? Doesn’t it licence a kind of anarchy where anything goes? Religious beliefs are on the same level as well tested scientific facts. 

HH: They may become dangerous, however, if they are presented as dogmas or as alleged necessities of thought. 

3:16: But how is science possible in such a situation? 

HH: Science must consider thoroughly all admissible hypotheses in order to obtain a complete picture of all possible modes of explanation. Furthermore, hypotheses are necessary to someone doing research, for one cannot always wait until a reliable scientific conclusion has been reached; one must sometimes make judgments according to either probability or aesthetic or moral feelings. Metaphysical hypotheses are not to be objected to here either. A thinker is unworthy of science, however, if he forgets the hypothetical origin of his assertions. The arrogance and vehemence with which such hidden hypotheses are sometimes defended are usually the result of a lack of confidence which their advocates feel in the hidden depths of their minds about the qualifications of their claims. 

3:16: The lawlike regularity of phenomena is important isn’t it. It’s because of these discovered regularities that we can draw scientific conclusions? 

HH: What we unquestionably can find as a fact, without any hypothetical element whatsoever, is the lawful regularity of phenomena. From the very first, in the case where we perceive stationary objects distributed before us in space, this perception involves the recognition of a uniform or law-like connection between our movements and the sensations which result from them. Thus even the most elementary ideas contain a mental element and occur in accordance with the laws of thought. everything that is added in intuition to the raw materials of sensation may be considered mental, provided of course that we accept the extended meaning of mental discussed earlier. 

3:16: So you’re with Schiller when he says the wise man ‘seeks for the familiar law amidst the awesome multiplicity of accidental occurrences, seeks for the eternal Pole Star amidst the constant flight of appearances,’ and all that jazz? 

HH: I am indeed Richard. The first product of the rational conception of phenomena is its lawfulness or regularity. If we have fully investigated some regularity, have established its conditions completely and with certainty and, at the same time, with complete generality, so that for all possible subsequent cases the effect is unequivocally determined - and if we have therefore arrived at the conviction that the law is true and will continue to hold true at all times and in all cases - then we recognise it as something existing independently of our ideas, and we label it a cause, or that which underlies or is behind the changes taking place. (Note that the meaning I give to the word cause and its application are both exactly specified, although in ordinary language the word is also variously used to mean antecedent or motive.) 

3:16: And what’s force? 

HH: Insofar as we recognise a law as a power analogous to our will, that is, as something giving rise to our perceptions as well as determining the course of natural processes, we call it a force. The idea of a force acting in opposition to us arises directly out of the nature of our simplest perceptions and the way in which they occur. From the beginning of our lives, the changes which we cause ourselves by the acts of our will are distinguished from those which are neither made nor can be set aside by our will. Pain, in particular, gives us the most compelling awareness of the power or force of reality. 

3:16: So this helps establish the sense of an objective world, that we aren’t just consciously bringing things into existence – that the world is separate from ourselves? 

HH: The emphasis falls here on the observable fact that the perceived circle of presentabilia is not created by a conscious act of our mind or will. Fichte's Non-Ego is an apt and precise expression for this. In dreaming, too, that which a person believes he sees and feels does not appear to be called forth by his will or by the known relations of his ideas, for these also may often be unconscious. They constitute a Non-Ego for the dreamer too. It is the same for the idealists who see the Non-Ego as the world of ideas of the World Spirit. 

We have in the German language a most appropriate word for that which stands behind the changes of phenomena and acts, namely, "the real". This word implies only action; it lacks the collateral meaning of existing as substance, which the concept of "the actual" or "the essential" includes. In the concept of "the objective", on the other hand, the notion of the complete form of objects is introduced, something that does not correspond to anything in our most basic perceptions. In the case of the logically consistent dreamer, it should be noted, we must use the words "effective" and "real" to characterise those Psychical conditions or motives whose sensations correspond uniformly to, and which are experienced as the momentary states of, his dreamed world. 

3:16: So objectivity is this sense that there are things we can alter and things we can’t and this comes from the perceived lawlike regularities we perceive? 

HH: Quite: it is clear that a distinction between thought and reality is possible only when we know how to make the distinction between that which the ego can and that which it cannot change. This, however, is possible only when we know the uniform consequences which volitions have in time. From this fact it can be seen that conformity to law is the essential condition which something must satisfy in order to be considered real. 

3:16: So objectivity isn’t perceiving things as they actually are but rather is a function of just having these regularities? 

HH: It is a contradictio in abjecto to try to present the actual or Kant's ding an sich in positive statements without comprehending it within our forms of representation. What we can attain, however, is knowledge of the lawful order in the realm of reality, since this can actually be presented in the sign system of our sense impressions. 

3:16: You like that Goethe understood this don’t you? 

HH: I take it to be a propitious sign that we find Goethe with us here, as well as further along on this same path. Whenever we are dealing with a question requiring a broad outlook, we can trust completely his clear, impartial view as to where the truth lies. He demanded of science that it be only an artistic arrangement of facts and that it form no abstract concepts concerning them, for he considered abstract concepts to be empty names which only hide the facts. In somewhat the same sense, Gustav Kirchhoff has recently stated that the task of the most abstract of the natural sciences, mechanics, is to describe completely and in the simplest possible way the kinds of motion appearing in nature. 

3:16: What do you say to those who think abstract concepts hide the facts? 

HH: this indeed happens if we remain in the realm of abstract concepts and do not examine their factual content, that is, if we do not try to make clear what new and observable invariant relations follow from them. A correctly formulated hypothesis, as we observed a moment ago, has its empirical content expressed in the form of a general law of nature. The hypothesis itself is an attempt to rise to more general and more comprehensive uniformities or regularities. Anything new, however, that an hypothesis asserts about facts must be established or confirmed by observation and experiment. Hypotheses which do not have such factual reference or which do not lead to trustworthy, unequivocal statements concerning the facts falling under them should be considered only worthless phrases. 

3:16: So abstract thoughts and the formation of concepts can be justified and are useful? 

HH: Every inductive inference is based upon a belief in the lawful regularity of everything that happens. This uniformity or lawful regularity, however, is also the condition of conceptual understanding. Thus belief in uniformity or lawful regularity is at the same time belief in the possibility of understanding natural phenomena conceptually. 

3:16: So we need these generalities? We can't just think in terms of individual things.

HH: Conceptual understanding, in the sense in which I have just described it, is the method by which the world is submitted to our thoughts, facts are ordered, and the future predicted. It is our right and duty to extend the application of this method to all occurrences, and significant results have already been achieved in this way. We have no justification other than its results, however, for the application of the law of causality. We might have lived in a world in which every atom was different from every other one and where nothing was stable. In such a world there would be no regularity whatsoever, and our conscious activities would cease. 

3:16: And our notion of causality is also something creatures like us need?

HH: The law of causality is in reality a transcendental law, a law which is given a priori. It is impossible to prove it by experience, for, as we have seen, even the most elementary levels of experience are impossible without inductive inferences, that is, without the law of causality. And even if the most complete experience should teach us that everything previously observed has occurred uniformly - a point concerning which we are not yet certain - we could conclude only by inductive inferences, that is, by presupposing the law of causality, that the law of causality will also be valid in the future. We can do no more than accept the proverb, "Have faith and keep on!" 

3:16: Nevertheless people might think that your theory means nothing we think about the world can be true. Are they right? 

HH: Goethe in Faust writes: ‘The earth's inadequacies Will then prove fruitful.’ That is the answer we must give to the question: what is true in our ideas? In giving this answer we find ourselves at the foundation of Kant's system and in agreement with what has always seemed to me the most fundamental advance in his philosophy. 

3:16: So you’d count yourself a Kantian in the grand scheme of things even if there are details you’d accept he got wrong – and importantly you see the natural sciences as bearing out the general picture he develops? 

HH: Oh yes. I have frequently noted in my previous works the agreement between the more recent physiology of the senses and Kant's teachings. I have not meant, of course, that I would swear in verbs magistri to all his more minor points. I believe that the most fundamental advance of recent times must be judged to be the analysis of the concept of intuition into the elementary processes of thought. Kant failed to carry out this analysis or resolution; this is one reason why he considered the axioms of geometry to be transcendental propositions. It has been the physiological investigations of sense perception which have led us to recognise the most basic or elementary kinds of judgment, to inferences which are not expressible in words. These judgments or inferences will, of course, remain unknown and inaccessible to philosophers as long as they inquire only into knowledge expressed in language. 

3:16: What about his relation to the possibility of metaphysics. Doesn’t Kant think metaphysics is compatible with his system whereas you’re pushing in the opposite direction aren’t you? 

HH: Kant's proof of the possibility of metaphysics, the alleged science he did nothing further to develop, rests completely upon the belief that the axioms of geometry and the related principles of mechanics are transcendental propositions, given a priori. As a matter of fact, however, Kant's entire system really conflicts with the possibility of metaphysics, and the more obscure points in his theory of knowledge, over which so much has been argued, stem from this conflict. Be that as it may, the natural sciences have a secure, well-established foundation from which they can search for the laws of reality, a wonderfully rich and fertile field of endeavour. As long as they restrict themselves to this search, they need not be troubled with any idealistic doubts. 

3:16: Like Goethe, you see both scientists and artists as people seeking a clear idea of the real don’t you? 

HH: The true scientist must always have something of the vision of an artist, something of the vision which led Goethe and Leonardo da Vinci to great scientific thoughts. Both artists and scientists strive, even if in different ways, toward the goal of discovering new uniformities or lawful regularities. But one must never produce idle swarms and mad fantasies in place of artistic vision. The true artist and the true scientist both know how to work steadily and how to give their work a convincing, truthful form. Moreover, reality has always unveiled the truth of its laws to the sciences in a much richer, more sublime fashion than she has painted it for even the most consummate efforts of mystical fantasy and metaphysical speculation. 

3:16: You’ve made important contributions to theories of dissonance and musical harmony haven’t you? Can you sketch for us what you have tried to establish? 

HH: I try to connect the boundaries of two sciences, which, although drawn towards each other by many natural afiinities, have hitherto remained practically distinct — I mean the boundaries of physical and physiological acoustics on the one side, and of musical science and esthetics on the other. 

3:16: This again shows that you don’t think separate academic traditions are helpful doesn’t it? 

HH: Yes. The horizons of physics, philosophy, and art have of late been too widely separated, and, as a consequence, the language, the methods, and the aims of any one of these studies present a certain amount of difficulty for the student of any of them; and possibly this is the principal cause why the problem here undertaken has not been long ago more thoroughly considered and advanced towards its solution. So up until now physical knowledge may indeed have been useful for musical instrument makers, but for the development and foundation of the theory of harmony it has hitherto been totally barren. And yet the essential facts within the field here to be explained and turned to account, have been known from the earliest times. 

Even Pythagoras knew that when strings of different lengths but of the same make, and subjected to the same tension, were used to give the perfect consonances of the Octave, Fifth, or Fourth, their lengths must be in the ratios of 1 to 2, 2 to 6, or 3 to 4 respectively, and if, as is probable, his knowledge was partly derived from the Egyptian priests, it is impossible to conjecture in what remote antiquity this law was first known. 

3:16: So your approach has been to unify these disciplines? 

HH: Yes. But in addition to a physical there is a physiological theory of acoustics the aim of which is to investigate the processes that take place within the ear itself.whilst the physical side of the theory of hearing has been already frequently attacked, the results obtained for its physiological and psychological sections are few, imperfect, and accidental. Yet it is precisely the physiological part in especial — the theory of the sensations of hearing — to which the theory of music has to look for the foundation of its structure. 

3:16: So you’re out to explain music without needing to begin with a theory of aesthetics. You’re arguing that there are certain blind physiological facts about us that explains why certain tones and beats strike us as being musical? 

HH: Yes. The question of how the ear is able to perceive these harmonic upper partial tones then leads to an hypothesis respecting the mode in which the auditory nerves are excited, which is well fitted to reduce all the facts and laws in this department to a relatively simple mechanical conception. The physiologico-physical investigation shows that two tones can be simultaneously heard by the ear without mutual disturbance, when and only when they stand to each other in the perfectly determinate and well-known relations of intervals which form musical consonance. We are thus immediately introduced into the field of music proper, and are led to discover the physiological reason for that enigmatical numerical relation announced by Pythagoras. 

The magnitude of the consonant intervals is independent of the quality of tone, but the harmoniousness of the consonances, and the distinctness of their separation from dissonances, depend on the quality of tone. The conclusions of physiological theory here agree precisely with the musical rules for the formation of chords ; they even go more into particulars than it was possible for the latter to do, and have, as I believe, the authority of the best composers in their favour. No attention is paid to aesthetic considerations. Natural phenomena obeying a blind necessity are alone treated. 

3:16: But you do get into aesthetics when you start to consider different tastes and the construction of musical scales and notes don’t you? 

HH: Right. Modern music has especially developed the principle of tonality, which connects all the tones in a piece of music by their relationship to one chief tone, called the tonic. On admitting this principle, the results of the preceding investigations furnish a method of constructing our modern musical scales and modes, from which all arbitrary assumption is excluded. I was unwilling to separate the physiological investigation from its musical consequences, because the correctness of these consequences must be to the physiologist a verification of the correctness of the physical and physiological views advanced, and anyone looking for musical conclusions alone, cannot form a perfectly clear view of the meaning and bearing of these consequences, unless he has endeavoured to get at least some conception of their foundations in natural science. 

3:16: So you’ve shown that particular tastes of harmonies and scales are driven by artistic not physiological concerns so its important to consider that different cultures and individuals are making artistic choices rather than deviating or conforming to a correct physiologically driven taste? 

HH: Yes. I have endeavoured to show that the construction of scales and of harmonic tissue is a product of artistic invention, and by no means furnished by the natural formation or natural function of our ear, as it has been hitherto most generally asserted. Just as people with differently directed tastes can erect extremely different kinds of buildings with the same stones, so also the history of music shows us that the same properties of the human ear could serve as the foundation of very different musical systems. Consequently it seems to me that we cannot doubt, that not merely the composition of perfect musical works of art, but even 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 the laws of artistic beauty. 

In point of fact, mankind has been at work on the diatonic system for more than 2500 years since the days of Terpander and Pythagoras, and in many cases we are still able to determine that the progressive changes made in the tonal system have been due to the most distinguished composers themselves, partly through their own independent inventions, and partly through the sanction which they gave to the inventions of others, by employing them artistically. 

3:16: And so aesthetics of music are connected with your theory of sensual perception and physiology. The big difficulty in discovering the laws of beauty is that they are hidden from consciousness isn’t it? 

HH: The difficulty consists in the fact that these laws and rules, on whose fulfilment beauty depends and by which it must be judged, are not consciously present to the mind, either of the artist who creates the work, or the observer who contemplates it. Art works with design, but the work of art ought to have the appearance of being undesigned, and must be judged on that ground. Art creates as imagination pictures, regularly without conscious law, designedly without conscious aim. A work, known and acknowledged as the product of mere intelligence, will never be accepted as a work of art, however perfect be its adaptation to its end. Whenever we see that conscious reflection has acted in the arrangement of the whole, we find it poor. 

3:16: But you don’t want it to be just accidental do you? 

HH: Exactly, we require every work of art to be reasonable, and we show this by subjecting it to a critical examination, and by seeking to enhance our enjoyment and our interest in it by tracing out the suitability, connection, and equilibrium of all its separate parts. Our endeavour to comprehend the beauty of such a work by critical examination, in which we partly succeed, shews that we assume a certain adaptation to reason in works of art, which may possibly rise to a conscious understanding, although such understanding is neither necessary for the invention nor for the enjoyment of the beautiful. 

3:16: And you also want it to be something beyond just an individual’s taste don’t you? 

HH: That we do not accept delight in the beautiful as something individual, but rather hold it to be in regular accordance with the nature of mind in general, appears by our expecting and requiring from every other healthy human intellect the same homage that we ourselves pay to what we call beautiful. At most we allow that national or individual peculiarities of taste incline to this or that artistic ideal, and are most easily moved by it, precisely in the same way that a certain amount of education and practice in the contemplation of fine works of art is undeniably necessary for penetration into their deeper meaning. 

3:16: So regularities are here just as important as they are in your theory of sensations ? 

HH: Yes. The principal difficulty in pursuing this object, is to understand how regularity can be apprehended by intuition without being consciously felt to exist. And this unconsciousness of regularity is not a mere accident in the effect of the beautiful on our mind, which may indifferently exist or not ; it is, on the contrary, most clearly, prominently, and essentially important. For through apprehending everywhere traces of regularity, connection, and order, without being able to grasp the law and plan of the whole, there arises in our mind a feeling that the work of art which we are contemplating is the product of a design which far exceeds anything we can conceive at the moment, and which hence partakes of the character of the illimitable. 

3:16: So it seems as if the artist is channelling a kind of aesthetic spirit because the mental powers in operation are hidden? 

HH: Indeed. We feel that those intellectual powers which were at work in the artist, are far above our conscious mental action, and that were it even possible at all, infinite time, meditation, and labour would have been necessary to attain by conscious thought that degree of order, connection, and equilibrium of all parts and all internal relations, which the artist has accomplished under the sole guidance of tact and  taste, and which we have in turn to appreciate and comprehend  our own tact and taste, long before we begin a critical analysis of the work. It is clear that all high appreciation of the artist and his work reposes essentially on this feeling. In the first we honour a genius, a spark of divine creative fire, which far transcends the limits of our intelligent and conscious forecast. 

3:16: And yet this is all explicable naturalistically? 

HH: Of course: the artist is a human being as we are, in whom work the same mental powers as in ourselves, only in their own peculiar direction, purer, brighter, steadier ; and by the greater or less readiness and completeness with which we grasp the artist's language we measure our own share of those powers which produced the wonder. 

3:16: But although we can understand this much it still remains essential to you that the inner mechanisms of the human mind remain hidden in a work of art, that this hiddenness is essential to its aesthetic value? 

HH: Yes. The contemplation of a real work of art awakens our confidence in the originally healthy nature of the human mind, when uncribbed, unharassed, unobscured, and unfalsified. But for all this it is an essential condition that the whole extent of the regularity and design of a work of art should not be apprehended consciously. It is precisely from that part of its regular subjection to reason, which escapes our conscious apprehension, that a work of art exalts and delights us, and that the chief effects of the artistically beautiful proceed, not from the part which we are able fully to analyse. 

3:16: And you show this in your theory of harmony and tone in music? 

HH: I have explained how musicians gradually discovered the relationships between tones and chords, and how the invention of harmonic music rendered these relationships closer, and clearer, and richer. We have been able to deduce the whole system of rules which constitute Thorough Bass, from an endeavour to introduce a clearly sensible connection into the series of tones which form a piece of music. 

3:16: The idea is that music is the refinement of normal, everyday hearing? 

HH: Exactly. Tones are not generally the subject of conscious perception as independent sensations. The conscious perception of everyday life is limited to the apprehension of the tone compounded of these partials, as a whole, just as we apprehend the taste of every compound dish as a whole, without clearly feeling how much of it is due to the salt, or the pepper, or other spices and condiments. A critical examination of our auditory sensations as such was required before we could discover the existence of upper partial tones. Hence the real reason of the melodic relationship of two tones (with the exception of a few more or less clearly expressed conjectures, as, for example, by Rameau and d'Alembert) remained so long undiscovered, or at least was not in any respect clearly and definitely formulated. 

I believe that I have been able to furnish the required explanation, and hence clearly to exhibit the whole connection of the phenomena. The aesthetic problem is thus related to the common property of all sensual perceptions, namely, the apprehension of compound aggregates of sensations as sensible symbols of simple external objects, without analysing them. 

3:16: So music is about focusing down if you like on these sounds we hear according to our physiology in everyday settings? 

HH: Right. In our usual observations on external nature our attention is so thoroughly engaged by external objects that we are entirely unpractised in taking for the subjects of conscious observation, any properties of our sensations themselves, which we do not already know as the sensible expression of some individual external object or event. 

3:16: And the development of harmony has been important in this? 

HH: The development of harmony gave rise to a much richer opening out of musical art than was previously possible, because the far clearer characterisation of related combinations of tones by means of chords and chordal sequences, allowed of the use of much more distant relationships than were previously available, by modulating into different keys. In this way the means of expression greatly increased as well as the rapidity of the melodic and harmonic transitions which could now be introduced without destroying the musical connection. As the independent significance of chords came to be appreciated in the fifteenth and sixteenth centuries, a feeling arose for the relationship of chords to one another and to the tonic chord, in accordance with the same law which had long ago unconsciously regulated the relationship of compound tones. 

The recognition of these resemblances between compound tones and between chords, reminds us of other exactly analogous circumstances which we must have often experienced. We recognise the resemblance between the faces of two near relations, without being at all able to say in what the resemblance consists, especially when age and sex are different, and the coarser outlines of the features consequently present striking differences. And yet notwithstanding these differences— notwithstanding that we are unable to fix upon a single point in the two countenances which is absolutely alike — the resemblance is often so extraordinarily striking and convincing, that we have not a moment's doubt about it. Precisely the same thing occurs in recognising the relationship between two compound tones. 

3:16: Again, it’s that inability to fix the resemblance precisely that is important isn’t it? 

HH: Yes. we are often able to assert with perfect certainty, that a passage not previously heard is due to a particular author or composer whose other works we know. Occasionally, but by no means always, individual mannerisms in verbal or musical phrases determine our judgment, but as a rule we are mostly unable to fix upon the exact points of resemblance between the new piece and the known works of the author or composer. The analogy of these different cases may be even carried farther. When a father and daughter are strikingly alike in some well-nicirked feature, as the nose or forehead, we observe it at once, and think no more about it. 

But if the resemblance is so enigmatically concealed that we cannot detect it, we are fascinated, and cannot help continuing to compare their countenances. And if a painter drew two such heads having, say, a somewhat different expression of character combined with a predominant and striking, though indefinable, resemblance, we should undoubtedly value it as one of the principal beatifies of his painting. Our admiration would certainly not be due merely to his technical skill ; we should rather look upon his painting as evidencing an unusually delicate feeling for the significance of the human countenance, and find in this the artistic justification of his work. Now the case is similar for musical intervals. 

3:16: You argue that space is important in understanding musical harmonies? 

HH: It is an essential character of space that at every position within it like bodies can be placed, and like motions can occur. Everything that is possible to happen in one part of space is equally possible in every other part of space and is perceived by us in precisely the same way. This is the case also with the musical scale. Such a close analogy consequently exists in all essential relations between the musical scale and space, that even alteration of pitch has a readily recognised and unmistakable resemblance to motion in space, and is often metaphorically termed the ascending or descending motion progression of a part. Hence, again, it becomes possible for motion in music to imitate the peculiar characteristics of forces in space, that is, to form an image of the various impulses and forces which lie at the root of motion. And on this, as I believe, essentially depends the power of music to picture emotion. 

3:16: Why don’t you think music initially just arises from people imitating the modulations of a voice in various emotional states as some have argued? 

HH: It is not my intention to deny that music in its initial state and simplest forms may have been originally an artistic imitation of the instinctive modulations of the voice that correspond to various conditions of the feelings. But I cannot think that this is opposed to the above explanation ; for a great part of the natural means of vocal expression may be reduced to such facts as the following : its rhythm and accentuation are an immediate expression of the rapidity or force of the corresponding psychical motives — all effort drives the voice up — a desire to make a pleasant impression on another mind leads to selecting a softer, pleasanter quality of tone — and so forth. 

An endeavour to imitate the involuntary modulations of the voice and make its recitation richer and more expressive, may therefore very possibly have led our ancestors to the discovery of the first means of musical expression, just as the imitation of weeping, shouting, or sobbing, and other musical delineations may play a part in even cultivated music (as in operas), although such modifications of the voice are not confined to the action of free mental motives, but embrace really mechanical and even involuntary muscular contractions. But it is quite clear that every completely developed melody goes far beyond an imitation of nature, even if we include the cases of the most varied alteration of voice under the influence of passion. Nay, the very fact that music introduces progression by fixed degrees both in rhythm and in the scale, renders even an approximately correct representation of nature simply impossible, for most of the passionate affections of the voice are characterised by a gliding transition in pitch. 

The imitation of nature is thus rendered as imperfect as the imitation of a picture by embroidery on a canvas with separate little squares for each shade of colour. Music, too, departed still further from nature when it introduced the greater compass, the mobility, and the strange qualities of tone belonging to musical instruments, by which the field of attainable musical effects has become so much wider than it was or could be when the human voice alone was employed. 

3:16: Finally, reflecting on your work which brings together philosophy and natural science, do you think we’re making enough progress in our philosophical and scientific endeavours? 

HH: We are particles of dust on the surface of our planet, which is itself scarcely a grain of sand in the infinite space of the universe. We are the youngest species among the living things of the earth, hardly out of the cradle according to the time reckoning of geology, still in the learning stage, hardly half-grown, said to be mature only through mutual agreement. Nevertheless, because of the mighty stimulus of the law of causality, we have already grown beyond our fellow creatures and are overcoming them in the struggle for existence. We truly have reason to be proud that it has been given to us to understand, slowly and through hard work, the incomprehensibly great scheme of things. Surely we need not feel in the least ashamed if we have not achieved this understanding upon the first flight of an Icarus.

Other Interviews: Heine, Rousseau, Cohen, Machiavelli, La Mettrie, Smith, Buchner,Lange, Newton, Berkeley, Hobbes, Locke, Cudworth, Hume, Leibniz, Leporin Erxleben, Fichte, Schiller, Herder, Kierkegaard, Schelling, Kant, Dilthey, Marx, Descartes, Hegel, Schopenhauer, Nietzsche

About the Author

Richard Marshall is still biding his time.