The twenty chapters of The Wonders of Life were written uninterruptedly in the course of four months which I spent at Rapallo, on the shore of the blue Mediterranean. The quiet life in this tiny coast-town of the Italian Riviera gave me leisure to weigh again all the views on organic life which I had formed by many-sided experience of life and learning since the beginning of my academic studies (1852) and my teaching at Jena (1861). To this I was stimulated by the constant sight of the blue Mediterranean, the countless inhabitants of which had, for fifty years, afforded such ample material for my biological studies; and my solitary walks in the wild gorges of the Ligurian Apennines, and the moving spectacle of its forest-crowned mountain altars, inspired me with a feeling of the unity of living nature—a feeling that only too easily fades away in the study of detail in the laboratory. On the other hand, such a situation did not allow a comprehensive survey of the boundless literature which has been evoked by the immense advances in every branch of biology. However, the present work is not intended to be a systematic manual of general biology. In the revision of the text, on which I was engaged during the summer at Jena, I had to restrict myself to occasional additions and improvements. In this I had the assistance of my worthy pupil, Dr. Heinrich Schmidt, to whom also I am indebted for the careful revision of the proofs.
When I completed my seventieth year at Rapallo, on February 16th, I was overwhelmed with a mass of congratulations, letters, telegrams, flowers, and other gifts, most of which came from unknown readers of The Riddle of the Universe in all parts of the world. If my thanks have not yet reached any of them, I beg to tender them in these lines. But I should be especially gratified if they would regard this work on the wonders of life as an expression of my thanks, and as a literary gift in return. May my readers be moved by it to penetrate deeper and deeper into the glorious work of Nature, and to reach the insight of our greatest German natural philosopher, Goethe:
"What greater thing in life can man achieve
Than that God-Nature be revealed to him?"
Ernst Haeckel.
Jena, June 17, 1904.
THE WONDERS OF LIFE