# Chapter III

My father had been promised by the management of the Southern Railway that he would be assigned to a small station near Vienna as soon as I should have finished at the *Realschule* and should need to attend the *Technische Hochschule*. In this way it would be possible for me to go to Vienna and return every day. So it happened that my family came to Inzersdorf am Wiener Berge. The station was at a distance from the town, very lonely, and in unlovely natural surroundings. My first visit to Vienna after we had moved to Inzersdorf was for the purpose of buying a greater number of philosophical books. What my heart was now especially devoted to was the first sketch of Fichte's *Wissenschaftslehre*.[^1] I had got so far with my reading of Kant that I could form a notion, even though immature, of the advance which Fichte wished to make beyond Kant. But this did not greatly interest me. What interested me then was to express the living weaving of the human mind in a sharply outlined mental picture. My strivings after conceptions in natural science had finally brought me to see in the activity of the human ego the sole starting-point for true knowledge. When the ego is active and itself perceives this activity, man has something spiritual in immediate presence in his consciousness – thus I said to myself. It seemed to me that what was thus perceived ought now to be expressed in clear, vivid concepts. In order to find a way to do this, I devoted myself to Fichte's *Theory of Science*. And yet I had my own opinions. So I took the volume and rewrote it, page by page. This made a lengthy manuscript. I had previously striven to find conceptions for the phenomena of nature from which one might derive a conception of the ego. Now I wished to do the opposite: from the ego to penetrate into the nature's process of becoming. Spirit and nature were present before my soul in their absolute contrast. There was for me a world of spiritual beings. That the ego, which itself is spirit, lives in a world of spirits was for me a matter of direct perception. But nature would not pass over into this spirit-world of my experience.

From my study of the *Theory of Science* I conceived a special interest in Fichte's treatises *Über die Bestimmung des Gelehrten*[^2] and *über das Wesen des Gelehrten*.[^3] In these writings I found a sort of ideal toward which I myself would strive. Along with these I read also the *Reden an die Deutsche Nation*.[^4] This took hold of me much less at that time than Fichte's other works.

But I wished now to come also to a better understanding of Kant than I had yet been able to attain. In the *Critique of Pure Reason* this understanding refused to be revealed to me. So I attacked the problem with the *Prolegomena zu einer jeden Künftigen Metaphysik*.[^5] Through this book I thought I recognized that a thorough penetration into all the questions which Kant had raised among thinkers was necessary for me. I now worked more consciously to the end that I might mould into the forms of *thought* the immediate vision of the spiritual world which I possessed. And while I was occupied with this inner work I sought to get my bearings with reference to the roads which had been taken by the thinkers of Kant's time and the succeeding epoch. I studied the dry, bald *Transcendentalen Synthetismus*[^6] of Traugott Krug just as eagerly as I entered into the tragedy of knowledge by which Fichte was possessed when he wrote his *Bestimmung des Menschen*.[^7] The history of philosophy by Thilo of the school of Herbart broadened my view of the evolution of philosophical thought from the period of Kant onward. I fought my way through to Schelling, to Hegel. The opposition between the thought of Herbart and of Fichte passed before my mind in all its intensity.

The summer months of 1879, from the end of my Realschule period until my entrance into the *Technische Hochschule*, I spent entirely in such philosophical studies. In the autumn I was to decide my choice of studies with reference to my future career. I decided to prepare to teach in a *Realschule*. The study of mathematics and descriptive geometry would have suited my inclination. But I should have to give up the latter; for the study of this subject required a great many practice hours during the day in geometrical drawings, but in order to earn some money I had to have leisure to devote to tutoring. This was possible while attending lectures whose subject-matter, when it was necessary to be absent from lectures, could afterwards be taken up in readings, but not possible when one had to spend hours assigned for drawing regularly in the school.

So I had myself enrolled for mathematics, natural history, and chemistry.

Of special import for me, however, were the lectures which Karl Julius Schröer gave at that time in the *Hochschule* on German literature. He lectured during my first year on “Literature since Goethe” and “Schiller's Life and Work.” From the very first lecture he impressed me. He developed a survey of the life of the spirit in Germany in the second half of the eighteenth century and placed in dramatic contrast with this Goethe's first appearance and its effect upon this spiritual life. The warmth of his manner of treating the subject, the inspiring way in which he entered into the selections read from the poets, introduced us through an inner process into the nature of poetry.

In connection with these lectures he had the habit of requiring “practice in oral and written lectures.” The students had then to deliver orally or read what they themselves had prepared. Schröer would give informal suggestions during these student performances as to style, manner of delivery, and the like. My first discussion dealt with Lessing's *Laokoon*. Then I undertook a longer paper. I worked up the theme: “To what extent is man in his actions a free being?” In connection with this paper I drew much upon Herbart's philosophy. Schröer did not like this at all. He had not shared in the enthusiasm for Herbart which then prevailed in Austria both in philosophical circles and also in pedagogy. He was devoted completely to Goethe's type of mind. So everything which was derived from Herbart seemed to him pedantic and prosaic, although he recognized the discipline of thought to be had from this philosopher.

I was now able to attend also certain lectures at the university. I took great satisfaction in the Herbartian, Robert Zimmermann. He lectured on “Practical Philosophy.” I attended that part of his lectures in which he developed the ground principles of ethics. I alternated, generally attending his lecture one day and the next that of Franz Brentano, who at the same period lectured on the same field. I could not keep this up very long, for I missed too much of the courses in the *Hochschule*.

I was deeply impressed by learning philosophy in this way, not merely out of books, but from the lips of the philosophers themselves.

Robert Zimmermann was a notable personality. He had an extraordinarily high forehead and a long philosopher's beard. With him everything was measured, reduced to style. When he entered through the door and mounted to his seat, his steps seemed to be studied, and all the more so because one felt: “With this man it is obviously natural to be like that.” In posture and movement he was as if he had formed himself thus through long discipline according to the aesthetic principles of Herbart. And yet one could entirely sympathize with all this. He then slowly sat down on the chair, cast a long glance through his spectacles over the auditorium, then slowly and precisely took off his glasses, looked once more for a long time without spectacles over the circle of auditors, and finally began to lecture, without manuscript but in carefully formed, artistically spoken sentences. There was something classic in his speech. Yet, owing to the long periods, one easily lost the thread of his discourse. He expounded Herbart's philosophy in a somewhat modified form. The close logic of his teaching impressed me. But it did not impress the other hearers. During the first three or four periods the great hall in which he lectured was full. “Practical Philosophy” was required for the law students in the first year. They needed the signature of the professor on their cards. From the fifth or sixth lecture on, most of them stayed away; while one listened to the classical philosopher, one was in a very small group of auditors on the farthest benches.

To me these lectures afforded a powerful stimulus, and the difference between the views of Schröer and Zimmermann interested me deeply. The little time I did not spend in attendance at lectures or in tutoring I utilized either in the *Hofbibliothek*[^8] or the library of the *Hochschule*. Then for the first time I read Goethe's *Faust*. In truth, until my nineteenth year, when I was inspired by Schröer, I had never been drawn to this work. Then, however, it won a strong claim upon my interest. Schröer had already begun his lectures on the first part. It happened that after only a few of the lectures I became better acquainted with Schröer. He then often took me to his home, told me this or that in amplification of his lectures, gladly answered my questions, and sent me away with a book from his library, which he lent me to read. In addition he said many things about the second part of Faust, an annotated edition of which he was already preparing. This part also I read at that time.

In the library I spent my time on Herbart's metaphysics through *Zimmermann's Aesthetic als Formwissenschaft*[^9] which was written from Herbart's point of view. Together with this I made a thorough study of Haeckel's *Generelle Morphologie*.[^10] I may say that everything which I felt to be entering into me through the lectures of Schröer and Zimmermann, as well as the reading I have mentioned, became a matter of the deepest mental experience. Riddles of knowledge and of world conception shaped themselves within me from these things.

Schröer was a spirit who cared nothing for system. He thought and spoke out of a certain intuition. Besides, he gave the greatest possible care to the manner in which he clothed his views in language. For this reason he almost never lectured without manuscript. He needed to write things down undisturbed in order himself to give the requisite attention to the bodying forth of this thought in appropriate words. Then he read a lecture in such a way as to bring into prominence its true inner meaning. Yet once he spoke extemporaneously about Anastasius Grün and Lenau. He had forgotten his manuscript. In the next period, however, he treated the whole topic again, reading from his manuscript. He was not satisfied with the form he had been able to give to the matter *extemporé*.

From Schröer I learned to understand many concrete examples of beauty. Through Zimmermann there came to me a developed theory of beauty. The two did not agree well. Schröer, the intuitive personality with a certain scorn for the systematic, stood before my mind side by side with Zimmermann, the rigidly systematic theorist of beauty.

Franz Brentano, whose lectures also on “Practical Philosophy” I attended, particularly interested me through his personality. He was a keen thinker and at the same time given to reverie. In his manner of lecturing there was something ceremonious. I listened to what he said, but I had also to observe every glance, every movement of his head, every gesture of his expressive hands. He was the perfect logician. Each thought must be absolutely complete and linked up with many other thoughts. The forms of these thought-series were determined by the most scrupulous attention to the requirements of logic. But I had the feeling that these thoughts did not come forth from the loom of his own mind; never did they penetrate into reality. And such also was the whole attitude of Brentano. He held the manuscript loosely in his hand as if at any moment it might slip from his fingers; with his glance he merely skimmed along the lines. And this was the action suited to a merely superficial touch upon reality, not for a firm grasp of it. I could understand his philosophy better from his “philosopher's hands” than from his words.

The stimulus which came from Brentano worked strongly upon me. I soon began to study his writings, and in the course of the following years read most of what he had published.

I felt in duty bound at that time to seek through philosophy for the truth. I had to study mathematics and natural science. I was convinced that I should find no relationship between these and myself unless I could place under them a solid foundation of philosophy. But I perceived a spiritual world, none the less, as a reality. In clear vision the spiritual individuality of every one revealed itself to me. This found in the physical body and in action in the physical world merely its manifestation. It united itself with that which came down as a physical germ from the parents. Dead men I followed farther on their way in the spiritual world. After the death of a schoolmate I wrote about this phase of my spiritual life to one of my former teachers, who had been a close friend of mine during my *Realschule* days. He wrote back to me with unusual affection; but he did not deign to say one word about what I had written regarding the dead schoolmate.

And this is what happened to me always at that time in this manner of my perception of the spiritual world. No one would pay any attention to it. From all directions persons would come with all sorts of spiritistic stuff. With this I in turn would have nothing to do. It was distasteful to me to approach the spiritual in such a way.

It then chanced that I became acquainted with a simple man of the plain people. Every week he went to Vienna by the same train that I took. He gathered medicinal plants in the country and sold them to apothecaries in Vienna. We became friends. With him it was possible to talk about the spiritual world as with one who had his own experience therein. He was a personality of inner piety. He was quite without schooling. He had read very many mystical books, but what he said was not at all influenced by this reading. It was the outflowing of a spiritual life which was marked by its own quite elementary creative wisdom. It was easy to perceive that he read these books only because he wished to find in others what he knew for himself. He revealed himself as if he, as a personality, were only the mouthpiece for a spiritual content which desired to utter itself out of hidden fountains. When one was with him one could get a glimpse deep into the secrets of nature. He carried on his back his bundle of medicinal plants; but in his heart he bore results which he had won from the spirituality of nature in the gathering of these herbs. I have seen many a man smile who now and then chanced to make a third party while I walked through the streets of Vienna with this “initiate.” No wonder; for his manner of expression was not to be understood at once. One had first in a certain sense to learn his spiritual dialect. To me also it was at first unintelligible. But from our first acquaintance I was in the deepest sympathy with him. And so I gradually came to feel as if I were in company with a soul of the most ancient times who – quite unaffected by the civilization, science, and general conceptions of the present age – brought to me an instinctive knowledge of earlier eras.

According to the usual conception of “learning,” one might say that it would be impossible to “learn” anything from this man. But, if one possessed in oneself a perception of the spiritual world, one might obtain glimpses very deep into this world through another who had a firm footing there. Moreover, anything of the nature of mere dreams was utterly foreign to this personality. When one entered his home, one was in the midst of the most sober and simplest family of country folk. Above the entrance to his home were the words: “With the blessing of God, all things are good.” One was entertained just as by other village people. I always had to drink coffee there, not from a cup, but from a porridge bowl[^11] which held nearly a litre; with this I had to eat a piece of bread of enormous dimensions. Nor did the villagers by any means look upon the man as a dreamer. There was no occasion for jesting at his behaviour in his village. Besides, he possessed a sound, wholesome humour, and knew how to chat, whenever he met with young or old of the village folk, in such fashion that the people liked to hear him talk. There was no one who smiled like those persons that watched him and me going together through the streets of Vienna, and these persons simply perceived in him some thing quite foreign to themselves.

This man always continued to be, even after life had taken me again far away from him, very close to me in soul. He appears in my mystery plays in the person of Felix Balde.

It was no light matter for my mental life at that time that the philosophy which I learned from others could not in its thought be carried all the way to the perception of the spiritual world. Because of the difficulty that I experienced in this respect, I began to fashion a form of “theory of knowledge” within myself. The life of thought in men came gradually to seem to me the reflection radiated into physical man from that which I experienced in the spiritual world. Thought experience was to me the thing itself with a reality into which – as something actually experienced through and through – doubt could find no entrance. The world of the senses did not seem to me so completely a matter of experience. It is there; but one does not lay hold upon it as upon thought. In it or behind it there might be an unknown reality concealed. Yet man himself is set in the midst of this world. Therefore, the question arises: Is *this* world, then, a reality complete in itself? When man from within weaves into this world of the senses the thoughts which bring light into this world, does he then bring into this world something foreign to it? This does not accord at all with the experience that man has when the world of the senses stands before him and he breaks into it by means of his thought. Thought then appears to be that by means of which the world of the senses expresses its own nature. The further development of this reflection was at that time a weighty part of my inner life.

But I wished to be prudent. To follow a course of thought too hastily to the extent of building up a philosophical view of one's own appeared to me a risky thing. This drove me to a thorough-going study of Hegel. The manner in which this philosopher set forth the reality of thought was distressing to me. That he made his way through only to a thought world, even though a living thought-world, and not to the perception of a world of concrete spirit – this repelled me. The assurance with which one philosophizes when one advances from thought to thought drew me on. I saw that many persons felt there was a difference between experience and thought. To me thought itself was experience, but of such a nature that one lived in it, not such that it entered from without into men. And so for a long time Hegel was very helpful to me.

As to my required studies, which in the midst of these philosophical interests had naturally to be cramped for time, it was fortunate for me that I had already occupied myself a great deal with differential and integral calculus and with analytical geometry. Because of this I could remain away from many lectures in mathematics without losing my connection. Mathematics was very important for me as the foundation under all my strivings after knowledge. In mathematics there is afforded a system of percepts and concepts which have been reached independently of any external sense impressions. And yet, said I to myself constantly at that time, one carries over these perceptions and concepts into sense-reality and discovers its laws. Through mathematics one learns to understand the world, and yet in order to do this one must first evoke mathematics out of the human mind.

A decisive experience came to me just at that time from the side of mathematics. The conception of space gave me the greatest inner difficulty. As the illimitable, all-encompassing vacuity – the form in which it lay at the basis of the dominant theories of natural science – it could not be conceived in any definite manner. Through the more recent (synthetic) geometry, which I learned by means of lectures and in private study, there came into my mind the perception that a line which should be prolonged endlessly toward the right hand would return again from the left to its starting-point. The infinitely distant point on the right is the same as the point infinitely distant on the left.

It came over me that by means of such conceptions of the newer geometry one might form a conception of space, which otherwise remained fixed in vacuity. The straight line returning upon itself like a circle seemed to be a revelation. I left the lecture at which this had first passed before my mind as if a great load had fallen from me. A feeling of liberation came over me. Again, as in my early boyhood, something satisfying had come to me out of geometry.

Behind the riddle of space stood at that period of my life the riddle of time. Might a conception be possible here also which would contain within itself in idea a return out of the past by way of an advance into the infinitely distant future? My happiness over the space conception caused a profound unrest over that of time. But there was then visible no way out. All efforts of thought led only to the realization that I must beware especially of applying the clear conception of space to the problem of time. All clarification which the striving for understanding could bring was frustrated by the riddle of time. The stimulus which I had received from Zimmermann toward the study of aesthetics led me to read the writings of the famous specialist in aesthetics of that time, Friedrich Theodor Vischer. I found in a passage of his work a reference to the fact that more recent scientific thought rendered necessary a change in the conception of time. There was always a sense of joy aroused in me when I found in others the recognition of any cognitional need which I had conceived. In this case it was like a confirmation in my struggle toward a satisfying concept of time.

The lectures for which I was enrolled in the *Technische Hochschule* I always had to finish with a corresponding examination. For a scholarship had been granted me, and I could draw my allowance only when I showed each year the results of my studies. But my need for understanding, especially in the sphere of natural science, was but little aided by these required studies. It was possible then, however, in the technical institutes of Vienna both to attend lectures as a visitor and also to carry on practical courses. I found everywhere those who met me half-way when I sought thus to foster my scientific life, even so far as to the study of medicine.

I may state positively that I never allowed my insight into the spiritual world to become a disturbing factor when I was engaged in the endeavour to understand science as it was then developed. I applied myself to what was taught, and only in the background of my thought did I have the hope that some day the blending of natural science with the knowledge of the spirit would be granted me.

Only from two sides was I disturbed in this hope.

The sciences of organic nature were then – wherever I could lay hold of them – steeped in Darwinian ideas. To me Darwinism appeared in its leading ideas as scientifically impossible. I had little by little reached the stage of forming for myself a conception of the inner man. This was of a spiritual sort. And this inner man I thought of as a member of the spiritual world. He was conceived as dipping down out of the spiritual world into nature, uniting with the organism of nature in order thereby to perceive and to act in the world of the senses.

The fact that I felt a certain respect for the course of thought characterizing the evolutionary theory of organisms did not render it possible for me to sacrifice anything from the conception. The derivation of higher out of lower organisms seemed to me a fruitful idea, but the identification of this idea with that which I knew as the spiritual world appeared to me immeasurably difficult.

The studies in physics were penetrated throughout by the mechanical theory of heat and the wave theory of the phenomena of light and colour.

The study of the mechanical theory of heat had taken on for me the charm of a personal colouring because in this field of physics I attended lectures by a personality for whom I felt quite extraordinary respect. This was Edmund Reitlinger, the author of that beautiful book, *Freie Blicke*.[^12]

This man was of the most captivating lovableness. When I became his student, he was already very seriously ill with tuberculosis. For two years I attended his lectures on the theory of heat, physics for chemists, and the history of physics. I worked under him in the physics laboratory in many fields, especially in that of spectrum-analysis.

Of special importance for me were Reitlinger's lectures on the history of physics. He spoke in such a way that one felt that, on account of his illness, every word was a burden to him. And yet his lectures were in the best possible sense inspiring. He was a man of a strongly inductive method of research. For all methods in physics he liked to cite the book of Whewel on inductive science. Newton marked for him the climax of research in physics. The history of physics he set forth in two parts: the first from the earliest times to Newton; the second from Newton to recent times. He was an universal thinker. From the historical consideration of problems in physics he always passed over to the perspective of the general history of culture. Indeed, quite general philosophic ideas would appear in his discussions of physics. In this way he treated the problems of optimism and pessimism, and spoke most impressively about the legitimacy of setting up scientific hypotheses. His exposition of Kepler, his characterization of Julius Robert Mayers, were masterpieces of scientific discussion.

I was then stimulated to read almost all the writings of Julius Robert Mayers, and I was able to experience the truly great pleasure of talking face to face with Reitlinger about the content of these.

I was filled with a deep sorrow when, only a few weeks after I had passed my final examination on the mechanical theory of heat under Reitlinger, my beloved teacher succumbed to his grievous illness. Just a short while before his death he had given me as his legacy a testimonial of personal qualifications which would enable me to secure pupils for private tutoring. This had most fortunate results. No small part of what came to me in the following years as means of livelihood I owed to Reitlinger after his death.

Through the mechanical theory of heat and the wave theory of light and of electric phenomena, I was impelled to a study of theories of cognition. At that time the external physical world was conceived as motion-events in matter. The sensations appeared to be only subjective experiences, as the effects of pure motion-events upon the senses of men. Out there in space occurred the motion-events in matter; if these events affected the human heat-sense, man experienced the sensation of heat. There are outside of man wave-events in the ether; if these affect the optic nerve, light and colour sensations are generated within man.

These conceptions met me everywhere. They caused me unspeakable difficulties in my thinking. They banished all spirit from the objective external world. Before my mind there stood the idea that even if the observations of natural phenomena led to such opinions, one who possessed a perception of the spiritual world could not arrive at these opinions. I saw how seductive these assumptions were for the manner of thought of that time, educated in the natural sciences, and yet I could not then resolve to oppose a manner of thought of my own against that which then prevailed. But just this caused me bitter mental struggles. Again and again must the criticism I could easily frame against this manner of thinking be suppressed within me to await the time in which more comprehensive sources and ways of knowledge should give me a greater assurance.

I was deeply stirred by the reading of Schiller's letters concerning the aesthetic education of man. His statement that human consciousness oscillates, as it were, back and forth between different states, afforded me a connection with the notion that I had formed of the inner working and weaving of the human soul. Schiller distinguished two states of consciousness in which man evolves his relationship to the world. When he surrenders himself to that which affects him through the senses, he lives under the compulsion of nature. The sensations and impulses determine his life. If he subjects himself to the logical laws and principles of reason then he is living under a rational compulsion. But he can evolve an intermediate state of consciousness. He can develop the “aesthetic mood,” which is not given over either on the one side to the compulsion of nature, or on the other to the necessities of the reason. In this aesthetic mood the soul lives through the senses; but into the sense-perception and into the action set on foot by sense-stimuli the soul brings over something spiritual. One perceives through the senses, but as if the spiritual had streamed over into the senses. In action one surrenders oneself to the gratification of the present desire; but one has so ennobled this desire that to him the good is pleasing and the evil displeasing. Reason has then entered into union with the sensible. The good becomes an instinct; instinct can safely direct itself, for it has taken on the character of the spiritual. Schiller sees in this state of consciousness that condition of the soul in which man can experience and produce works of beauty. In the evolution of this state he sees the coming to life in men of the true human being.

These thoughts of Schiller's were to me very attractive. They implied that man must first have his consciousness in a certain condition before he can attain to a relationship to the phenomena of the world corresponding to man's own being. Something was here given to me which brought to greater clarity the questions which presented themselves before me out of my observation of nature and my spiritual experience. Schiller spoke of the state of consciousness which must be present in order that one may experience the beauty of the world. Might one not also think of a state of consciousness which would mediate to us the truth in the beings of things? If this is granted, then one must not, after the fashion of Kant, observe the present state of human consciousness and investigate whether this can enter into the true beings of things. But one must first seek to discover the state of consciousness through which man places himself in such a relationship to the world that things and facts reveal their being to him.

And I believed that I knew that such a state of consciousness is reached up to a certain degree when man not only has thoughts which conceive external things and events, but *such thoughts that he himself experiences them as thoughts*. This living in thoughts revealed itself to me as quite different from that in which man ordinarily exists and also carries on ordinary scientific research. If one penetrates deeper and deeper into thought-life, one finds that spiritual reality comes to meet this thought life. One then takes the path of the soul into the spirit. But on this inner way of the soul one arrives at a spiritual reality which one also finds again within nature. One gains a deeper knowledge of nature when one then faces nature after having in living thoughts beheld the reality of the spirit.

It became clearer and clearer to me how, through going forward beyond the customary abstract thoughts to these spiritual perceptions – which, however, the calmness and luminousness of the thought serve to confirm – man lives himself into a reality from which customary consciousness bars him out. This customary state has on one side the living quality of the sense-perception; on the other the abstractness of thought-conceiving. The spiritual vision perceives spirit as the senses perceive nature; but it does not stand apart in thought from the spiritual perception as the customary state of consciousness stands in *its* thoughts apart from the sense-perceptions. Spiritual vision thinks while it experiences spirit, and experiences while it sets to thinking the awakened spirituality of man.

A spiritual perception formed itself before my mind which did not rest upon dark mystical feeling. It proceeded much more in a spiritual activity which in its thoroughness might be compared with mathematical thinking. I was approaching the state of soul in which I felt that I might consider that the perception of the spiritual world which I bore within me was confirmed before the forum of natural scientific thought.

When these experiences passed through my mind I was in my twenty-second year.

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[^1]: *Theory of Science.*

[^2]: *The Vocation of the Scholar.*

[^3]: *The Nature of the Scholar.*

[^4]: *Addresses to the German Nation.*

[^5]: *Prolegomena to all Future Metaphysics*

[^6]: *Transcendental Synthesism.*

[^7]: *Destiny of Man.*

[^8]: The Public Library.

[^9]: Ii>Aesthetics as the Science of Form.

[^10]: *General Morphology.*

[^11]: *THöferl.*

[^12]: .Open Vistas