The Riddle of the Universe by Ernst Haeckel

(...)"AUTHOR'S PREFACE

"THE present study of the monistic philosophy is * intended for thoughtful readers of every condition who are united in an honest search for the truth. An intensification of this effort of man to attain a knowledge of the truth is one of the most salient features of the nineteenth century. That is easily explained, in the first place, by the immense progress of science, especially in its most important branch, the history of humanity; it is due, in the second place, to the open contradiction that has developed during the century between(...)".

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