Astrology and the Like. – It is probable that the objects of religious, moral, æsthetic and logical sentiment likewise belong only to the surface of things, while man willingly believes that here, at least, he has touched the heart of the world; he deceives himself, because those things enrapture him so profoundly, and make him so profoundly unhappy, and he therefore shows the same pride here as in astrology. For astrology believes that the firmament moves round the destiny of man; the moral man, however, takes it for granted that what he has essentially at heart must also be the essence and heart of things.
Misunderstanding of Dreams. – In the ages of a rude and primitive civilisation man believed that in dreams he became acquainted with a second actual world; herein lies the origin of all metaphysics. Without dreams there could have been found no reason for a division of the world. The distinction, too, between soul and body is connected with the most ancient comprehension of dreams, also the supposition of an imaginary soul-body, therefore the origin of all belief in spirits, and probably also the belief in gods. "The dead continues to live, for he appears to the living in a dream": thus men reasoned of old for thousands and thousands of years.
The Scientific Spirit Partially But Not Wholly Powerful. – The smallest subdivisions of science taken separately are dealt with purely in relation to themselves, – the general, great sciences, on the contrary, regarded as a whole, call up the question – certainly a very non-objective one – "Wherefore? To what end?" It is this utilitarian consideration which causes them to be dealt with less impersonally when taken as a whole than when considered in their various parts. In philosophy, above all, as the apex of the entire, pyramid of science, the question as to the utility of knowledge is involuntarily brought forward, and every philosophy has the unconscious intention of ascribing to it the greatest usefulness. For this reason there is so much high-flying metaphysics in all philosophies and such a shyness of the apparently unimportant solutions of physics; for the importance of knowledge for life must appear as great as possible. Here is the antagonism between the separate provinces of science and philosophy. The latter desires, what art does, to give the greatest possible depth and meaning to life and actions; in the former one seeks knowledge and nothing further, whatever may emerge thereby. So far there has been no philosopher in whose hands philosophy has not grown into an apology for knowledge; on this point, at least, every one is an optimist, that the greatest usefulness must be ascribed to knowledge. They are all tyrannised over by logic, and this is optimism – in its essence.
The Kill-joy in Science. – Philosophy separated from science when it asked the question, "Which is the knowledge of the world and of life which enables man to live most happily?" This happened in the Socratic schools; the veins of scientific investigation were bound up by the point of view of happiness,– and are so still.
Pneumatic Explanation of Nature. – Metaphysics explains the writing of Nature, so to speak, pneumatically, as the Church and her learned men formerly did with the Bible. A great deal of understanding is required to apply to Nature the same method of strict interpretation as the philologists have now established for all books with the intention of clearly understanding what the text means, but not suspecting a double sense or even taking it for granted. Just, however, as with regard to books, the bad art of interpretation is by no means overcome, and in the most cultivated society one still constantly comes across the remains of allegorical and mystic interpretation, so it is also with regard to Nature, indeed it is even much worse.
The Metaphysical World. – It is true that there might be a metaphysical world; the absolute possibility of it is hardly to be disputed. We look at everything through the human head and cannot cut this head off; while the question remains, What would be left of the world if it had been cut off? This is a purely scientific problem, and one not very likely to trouble mankind; but everything which has hitherto made metaphysical suppositions valuable, terrible, delightful for man, what has produced them, is passion, error, and self-deception; the very worst methods of knowledge, not the best, have taught belief therein. When these methods have been discovered as the foundation of all existing religions and metaphysics, they have been refuted. Then there still always remains that possibility; but there is nothing to be done with it, much less is it possible to let happiness, salvation, and life depend on the spider-thread of such a possibility. For nothing could be said of the metaphysical world but that it would be a different condition, a condition inaccessible and incomprehensible to us; it would be a thing of negative qualities. Were the existence of such a world ever so well proved, the fact would nevertheless remain that it would be precisely the most irrelevant of all forms of knowledge: more irrelevant than the knowledge of the chemical analysis of water to the sailor in danger in a storm.
The Harmlessness of Metaphysics in the Future. – Directly the origins of religion, art, and morals have been so described that one can perfectly explain them without having recourse to metaphysical concepts at the beginning and in the course of the path, the strongest interest in the purely theoretical problem of the "thing-in-itself" and the "phenomenon" ceases. For however it may be here, with religion, art, and morals we do not touch the "essence of the world in itself"; we are in the domain of representation, no "intuition" can carry us further. With the greatest calmness we shall leave the question as to how our own conception of the world can differ so widely from the revealed essence of the world, to physiology and the history of the evolution of organisms and ideas.
Language As a Presumptive Science. – The importance of language for the development of culture lies in the fact that in language man has placed a world of his own beside the other, a position which he deemed so fixed that he might therefrom lift the rest of the world off its hinges, and make himself master of it. Inasmuch as man has believed in the ideas and names of things as æternæ veritates for a great length of time, he has acquired that pride by which he has raised himself above the animal; he really thought that in language he possessed the knowledge of the world. The maker of language was not modest enough to think that he only gave designations to things, he believed rather that with his words he expressed the widest knowledge of the things; in reality language is the first step in the endeavour after science. Here also it is belief in ascertained truth, from which the mightiest sources of strength have flowed. Much later – only now – it is dawning upon men that they have propagated a tremendous error in their belief in language. Fortunately it is now too late to reverse the development of reason, which is founded upon that belief. Logic, also, is founded