Our scientific theories, too, are no longer to be formulated as if we were unconditionally compelled to accept them. None of us would wish to give a scientific work a title like Fichte's A Pellucid Account for the General Public concerning the Real Nature of the Newest Philosophy. An Attempt to Compel the Readers to Understand. Nowadays there is no attempt to compel anyone to understand. We claim no agreement from anyone whom a distinct individual need does not drive to a certain view. We do not seek nowadays to cram facts of knowledge even into the immature human being, the child. We seek rather to develop his faculties in such a way that his understanding may depend no longer on our compulsion, but on his will. I am under no illusion concerning the characteristics of the present age. I know how many flaunt a manner of life which lacks all individuality and follows only the prevailing fashion. But I know also that many of my contemporaries strive to order their lives in the direction of the principles I have indicated. To them I would dedicate this book. It does not pretend to offer the "only possible" way to Truth, it only describes the path chosen by one whose heart is set upon Truth. The reader will be led at first into somewhat abstract regions, where thought must draw sharp outlines, if it is to reach secure conclusions. But he will also be led out of these arid concepts into concrete life. I am fully convinced that one cannot do without soaring into the ethereal realm of abstraction, if one's experience is to penetrate life in all directions. He who is limited to the pleasures of the senses misses the sweetest enjoyments of life. The Oriental sages make their disciples live for years a life of resignation and asceticism before they impart to them their own wisdom. The Western world no longer demands pious exercises and ascetic practices as a preparation for science, but it does require a sincere willingness to withdraw oneself awhile from the immediate impressions of life, and to betake oneself into the realm of pure thought.