This thought conflicts with a common prejudice which is very hard to overcome. The victims of this prejudice are unable to see that the concept of a triangle which my mind grasps is the same as the concept which my neighbour’s mind grasps. The naïve man believes himself to be the creator of his concepts. Hence he believes that each person has his private concepts. One of the first things which philosophic thought requires of us is to overcome this prejudice. The one single concept of “triangle” does not split up into many concepts because it is thought by many minds. For the thought of the many is itself a unity.
In thought we have the element which welds each man’s special individuality into one whole with the cosmos. In so far as we sense and feel (perceive), we are isolated individuals; in so far as we think, we are the All-One Being which pervades everything. This is the deeper meaning of our two-sided nature. We are conscious of an absolute principle revealing itself in us, a principle which is universal. But we experience it, not as it issues from the centre of the world, but rather at a point on the periphery. Were the former the case, we should know, as soon as ever we became conscious, the solution of the whole world problem. But since we stand at a point on the periphery, and find that our own being is confined within definite limits, we must explore the region which lies beyond our own being with the help of thought, which is the universal cosmic principle manifesting itself in our minds.
The fact that thought, in us, reaches out beyond our separate existence and relates itself to the universal world-order, gives rise to the desire for knowledge in us. Beings without thought do not experience this desire. When they come in contact with other things no questions arise for them. These other things remain external to such beings. But in thinking beings the concept confronts the external thing. It is that part of the thing which we receive not from without, but from within. To assimilate, to unite, the two elements, the inner and the outer, that is the function of knowledge.
The percept, thus, is not something finished and self-contained, but one side only of the total reality. The other side is the concept. The act of cognition is the synthesis of percept and concept. And it is only the union of percept and concept which constitutes the whole thing.
The preceding discussion shows clearly that it is futile to seek for any other common element in the separate things of the world than the ideal content which thinking supplies. All attempts to discover any other principle of unity in the world than this internally coherent ideal content, which we gain for ourselves by the conceptual analysis of our percepts, are bound to fail. Neither a personal God, nor force, nor matter, nor the blind will (of Schopenhauer and Hartmann), can be accepted by us as the universal principle of unity in the world. These principles all belong only to a limited sphere of our experience. Personality we experience only in ourselves, force and matter only in external things. The will, again, can be regarded only as the expression of the activity of our finite personalities. Schopenhauer wants to avoid making “abstract” thought the principle of unity in the world, and seeks instead something which presents itself to him immediately as real. This philosopher holds that we can never solve the riddle of the world so long as we regard it as an “external” world. “In fact, the meaning for which we seek of that world which is present to us only as our idea, or the transition from the world as mere idea of the knowing subject to whatever it may be besides this, would never be found if the investigator himself were nothing more than the pure knowing subject (a winged cherub without a body). But he himself is rooted in that world: he finds himself in it as an individual, that is to say, his knowledge, which is the necessary supporter of the whole world as idea, is yet always given through the medium of a body, whose affections are, as we have shown, the starting-point for the understanding in the perception of that world. His body is, for the pure knowing subject, an idea like every other idea, an object among objects. Its movements and actions are so far known to him in precisely the same way as the changes of all other perceived objects, and would be just as strange and incomprehensible to him if their meaning were not explained for him in an entirely different way …. The body is given in two entirely different ways to the subject of knowledge, who becomes an individual only through his identity with it. It is given as an idea in intelligent perception, as an object among objects and subject to the laws of objects. And it is also given in quite a different way as that which is immediately known to every one, and is signified by the word ‘will.’ Every true act of his will is also at once and without exception a movement of his body. The act of will and the movement of the body are not two different things objectively known, which the bond of causality unites; they do not stand in the relation of cause and effect; they are one and the same, but they are given in entirely different ways—immediately, and again in perception for the understanding.” (The World as Will and Idea, Book 2, § 18.) Schopenhauer considers himself entitled by these arguments to hold that the will becomes objectified in the human body. He believes that in the activities of the body he has an immediate experience of reality, of the thing-in-itself in the concrete. Against these arguments we must urge that the activities of our body become known to us only through self-observation, and that, as such, they are in no way superior to other percepts. If we want to know their real nature, we can do so only by means of thought, i.e., by fitting them into the ideal system of our concepts and ideas.
One of the most deeply rooted prejudices of the naïve mind is the opinion that thinking is abstract and empty of any concrete content. At best, we are told, it supplies but an “ideal” counterpart of the unity of the world, but never that unity itself. Whoever holds this view has never made clear to himself what a percept apart from concepts really is. Let us see what this world of bare percepts is. A mere juxtaposition in space, a mere succession in time, a chaos of disconnected particulars—that is what it is. None of these things which come and go on the stage of perception has any connection with any other. The world is a multiplicity of objects without distinctions of value. None plays any greater part in the nexus of the world than any other. In order to realise that this or that fact has a greater importance than another we must go to thought. As long as we do not think, the rudimentary organ of an animal which has no significance in its life, appears equal in value to its more important limbs. The particular facts reveal their meaning, in themselves and in their relations with other parts of the world, only when thought spins its threads from thing to thing. This activity of thinking has always a content. For it is only through a perfectly definite concrete content that I can know why the snail belongs to a lower type of organisation than the lion. The mere appearance, the percept, gives me no content which could inform me as to the degree of perfection of the organisation.
Thought contributes this content to the percept from the world of concepts and ideas. In contrast with the content of perception which is given to us from without, the content of thought appears within our minds. The form in which thought first appears in consciousness we will call “intuition.” Intuition is to thoughts what observation is to percepts. Intuition and observation are the sources of our knowledge. An external object which we observe remains unintelligible to us, until the corresponding intuition arises within us which adds to the reality those sides of it which are lacking in the percept. To anyone who is incapable of supplying the relevant intuitions, the full nature of the real remains a sealed book. Just as the colour-blind person sees only differences of brightness without any colour qualities, so the mind which lacks intuition sees only disconnected fragments of percepts.
To explain a thing, to make it intelligible, means nothing else than to place it in the context from which it has been torn by the peculiar organisation of our minds, described above. Nothing can possibly exist cut off from the universe. Hence all isolation of objects has only subjective validity for minds organised like ours. For us the universe is split up into above and below, before and after, cause and effect, object and idea, matter and force, object and subject, etc. The objects which, in observation, appear to us as separate, become combined, bit by bit, through the coherent, unified system of our intuitions. By thought we fuse again into one whole all that perception has separated.
An object presents riddles to our understanding so long as it exists in isolation. But this is an abstraction of our own making and can be unmade again in the world of concepts.
Except through thought and perception nothing is given to us directly. The question now arises as to the interpretation of percepts on our theory. We have learnt that the proof which Critical Idealism offers for the subjective nature of percepts collapses. But the exhibition of the falsity of the proof is not, by itself, sufficient to show that the doctrine itself is an error. Critical Idealism does not base its proof on the absolute nature of thought, but relies on the argument that Naïve Realism, when followed to its logical conclusion, contradicts itself. How does the matter appear when we recognise the absoluteness of thought?