Plato expresses this distrust in experience with his own admirable courage. “The things of this world which our senses perceive have no real existence: they are always becoming, they never are. Theirs is only a relative existence; taken together, they exist only in and by virtue of their relation to each other; hence we can with equal truth say of their whole existence that it is Non-Existence. Hence they are not objects of a real knowledge. There can only be real knowledge of something that exists in and for itself, and ever the same way, whereas these sense-phenomena are only the objects of conjecture evoked by sensation. So long as we are restricted to the perception of these things we are like men in a dark cave, bound so rigidly that they cannot even turn the head, seeing nothing except when the light of a fire burning behind them throws on the wall in front the shadows of real objects which pass between them and the fire; each man sees only the shadows of the other, only the shadow of himself on that wall. But the wisdom of such men would consist in predicting the sequence of those shadows as taught them by experience.”
Platonism tears the perception (Vorstellung) of the universe into two parts: the perception of the world of appearance and that of the world of ideas, and true, eternal reality is supposed to correspond only to the latter. “That which alone may be said to have true existence, because it always is, neither becoming nor passing away, is the ideal Archetype of each shadow picture, the eternal idea, the archetypal form of each object. These eternal ideas undergo no multiplicity, for each in its true nature is one and one alone; it is the archetype whose reflections or shadows picture are all homonymous, single, transitory things of the same nature. These eternal ideas do not arise, neither do they pass away; they truly are, they do not become nor pass away like their transitory reflections. Hence of them alone can there be a real knowledge, for the object of a real knowledge can only be that which is eternally and in every respect, not that which is and again is not, according to how it is perceived.”
It is only justifiable to make a distinction between ideas and perception when we are speaking of the way in which human cognition arises. Man must allow the objects to speak to him in a twofold sense. They communicate one part of their being to him voluntarily, and he need only pay attention. This is the part of reality that is free of ideas. The other part, however, he must himself extract from the objects. He must set thought in action and then his inner being is flooded with the ideas of the objects. The stage whereon objects reveal their inner, ideal content, is within the personality. They there make manifest that which is forever concealed from external perception. The true being of Nature here becomes articulate. It is due to the constitution of the human organisation that objects can only be cognised through the consonance of two tones. In Nature we have one exitant producing both tones. The open-minded man listens for the consonance. In the ideal speech of his inmost being he recognises the utterances which the objects make to him. Only those who are no longer open-minded interpret the matter otherwise. They believe that the speech of their inmost being proceeds from a sphere other than that of the speech of external perception. Plato realised how important it is for man's world-conception that the universe is revealed to him from two sides. His understanding appreciation of this fact made him recognise that reality may not be ascribed to the sense-world per se. Only when the world of ideas lights up from out of the life of soul and in his contemplation of the world man is able to set before his spirit, idea and sense perception as a uniform, cognitional experience, has he true reality before him. That which confronts sense-perception without being irradiated by the light of the world of ideas, is a world of appearance. In this sense Plato's insight also sheds light on Parmenides' view concerning the illusory nature of sense objects. It may well be said that Plato's philosophy is one of the most sublime thought-structures that have ever emanated from the mind of man. Platonism represents the conviction that the goal of all striving after knowledge must be the assimilation of the ideas that support the world and constitute its foundations. A man who cannot awaken this conviction in himself has no understanding of the Platonic view of the world. So far as Platonism has entered into the evolution of Western thought, however, it reveals yet another aspect. Plato did not only stress the knowledge that so far as human perception is concerned the sense world becomes mere appearance when the light of the world of ideas is not shed upon it, but his presentation of this fact has furthered the notion that the sense world in itself, apart altogether from man, is a world of appearance, and that true reality is to be found only in the ideas. Out of this notion the question arises: How do ideas and the world of sense (Nature) outside man coincide? Those who cannot admit the existence of a sense world, free of ideas, outside man, must seek for and solve the problem of the relationship of idea and sense world within the being of man. And this is how the matter stands before the Goethean world-conception. The question, “What is the relationship outside man between idea and sense world?” is, so far as this world-conception is concerned, unsound, because for it there exists outside man no sense world (Nature) apart from idea. Man alone can for himself separate ideas from the world of sense and so conceive Nature void of ideas. It may therefore be said that in the Goethean world-conception the question which has occupied the evolution of Western thought for centuries as to how idea and sense-object come together, is utterly superfluous. And the outcome of this current of Platonism in the evolution of Western thought which Goethe encountered in the above-mentioned conversations with Schiller, for example, and also elsewhere, seemed to him an unhealthy element in human thought. The view that he did not definitely put into words but which lived in his perception and was a formative impulse in his own world-conception was this: healthy human feeling teaches us at every moment how the languages of perception and of thought unite in order to reveal the full reality, and this has been ignored by the speculative thinkers. Instead of paying attention to the way in which Nature speaks to man, they have built up artificial concepts of the relationship of the world of ideas and experience. In order to realise fully what deep significance this trend of thought, considered by Goethe to be unsound, had in the world-conception which confronted him and from which he would have liked to take his bearings, we must bear in mind how this current of Platonism which dissipates the sense world into appearance and so brings the world of ideas into a distorted relationship to it, has been strengthened as the result of a one-sided philosophical interpretation of Christian truth in the course of the evolution of Western thought. It was because of the fact that Goethe encountered Christian conceptions bound up with this, to him, unhealthy current of Platonism, that he could only with difficulty build up his relationship to Christianity. Goethe has not followed up in detail the further influence of this current of Platonism (which he discarded) in the evolution of Christian thought, but he perceived its influence in the modes of thought which he encountered. As a result of this, light is thrown on the development of Goethe's mode of conception by observation that is able to trace the growth of this influence in the directions taken by thought through the centuries prior to Goethe. The evolution of Christian thought as shown in many of its exponents, endeavoured to come to terms with the belief in the world Beyond and with the value that sense existence has in relation to the spiritual world. Those who adhered to the conception that the relation of the sense world to the world of ideas has a significance apart altogether from man, arrived, together with the problems arising out of this, at the conception of a Divine World Order. And Church Fathers, faced with this problem, had to cogitate on the role played by the Platonic world of ideas within this Divine World Order. Here there arose the danger of conceiving idea and sense world (which are united in human cognition through direct perception) not only as being separated off from man in themselves, but separated from each other, so that the ideas, apart from what is given to man in Nature, lead an independent existence of their own in a spirituality separated from Nature. When this conception, which is based on a false view of the world of ideas and the sense world, was added to the justifiable opinion that the Divine can never live in full consciousness in the human soul, the result was a complete severance of the world of ideas and Nature from each other. That which ought always to be sought within the spirit of man is then sought outside it in creation. The Archetypes of all objects are thought to be contained within the Divine Spirit. The world becomes the imperfect reflection of the perfect world of ideas resting in God. As a result, then, of a one-sided understanding of Platonism, the human soul is separated from the relationship existing between idea and “reality.” The soul extends its rightly conceived relationship to the Divine World Order to the relationship existing within itself between the world of ideas and the world of sense appearance. This mode of conception leads Augustine to the following view: “We can believe without hesitation that although the thinking soul is not of like nature to God, since He permits of no communion, the soul may indeed be illuminated as the result of participation in the Divine Nature.” And so when this particular mode of conception is carried to extremes, it is no longer possible for the human soul in its contemplation of Nature to experience the world of ideas as the essence of reality. Such experience is designated unchristian. The one-sided conception of Platonism is extended to Christianity itself. Platonism, as a philosophical view of the world remains more within the element of thought; religious experience plunges thought into the life of feeling and establishes it thus in man's nature. Grappled in this way to the soul life of man, the unsound element of a one-sided Platonism was able to assume a deeper significance in the Western evolution of thought than would have been the case if it had remained pure philosophy. For centuries this thought-evolution confronted questions such as: What relation is there between that which man builds up as idea and objects of reality? Are the living concepts existing in the human soul through the world of ideas only notions, names, that have nothing to do with reality? Have these concepts within them something real that enters into man when he becomes aware of reality and comprehends it through his intelligence? So far as the Goethean world-conception is concerned such questions are not reasonable in reference to anything that lies outside the scope of man's being. In man's perception of reality these problems are resolved through true human cognition in eternal, living essence. And the Goethean world-conception has not only to come to the conclusion that an element of a one-sided Platonism lives in Christian thought but it has a feeling of estrangement even from true Christianity itself when this appears before it saturated with such Platonism. In many of the thoughts that Goethe developed, in order to make the world intelligible to himself, there lived this element of aversion from the current of Platonism that he felt to be unsound. That he had, also, an open mind for the way in which Platonism raises the soul of man to the world of ideas is proved by many an utterance of his in this connection. He felt in himself the activity of the real world of ideas while observing and investigating Nature in his own way; he felt that Nature herself speaks in the language of ideas when the soul opens itself to such language. But he could not admit that the world of ideas may be considered as something separate and apart, and that it is possible, as a result of this, to say of an idea of the plant-being, that this is not an experience but an idea. For Goethe felt that his spiritual eye perceived the idea as reality, just as the eye of sense sees the physical part of the plant-being. In this sense the orientation of Platonism towards the world of ideas entered into the Goethean world-conception in its purity and the current of Platonism that leads away from reality was there overcome. As the result of this configuration of his world-conception Goethe had also to reject so-called “Christian” conceptions which had assumed a form that could only appear to him as transformed and one-sided Platonism. And he was, moreover, bound to feel that many of the world-conceptions confronting him and with which he would have liked to come to terms, had not been able in Western culture to overcome this Christian-Platonic view of reality that is not in conformity with Nature and Ideal.