A remarkable tribute of world-wide affection is the volume issued on his eightieth birthday, "Was wir Ernst Haeckel verdanken" (Leipzig: Verlag Unesma), to which one hundred and twenty-five men and women contributed,—savants, artists, workingmen, officials, and businessmen.
The monistic movement may be followed by the pamphlets of the society which may be obtained ordinarily from the Verlag Unesma, Leipzig. Some of the more interesting of these Flugschriften are: "Friedrich Paulsen über Ernst Haeckel", by Albrecht Rau; "Reinke contra Haeckel", by Heinrich Schmidt; "Eine neue Reformation vom Christentum zum Monismus", by Hannah Dorsch and Arnold Dodel; "Monismus und Christentum", by Heinrich Schmidt; "Monismus und Klerikalismus", by J. Unold; "Das Einheit der physikochemischen Wissenschaften", by Wilhelm Ostwald; "Die einheitliche Weltanschauung", by Ernst Diesing: this last urges the Monists to support the peace and conservation movements. The official organ is Das monistische Jahrhundert, a weekly edited by Ostwald and published by the Verlag Unesma, Leipzig. The issue for February 14, 1914, is, in honor of his eightieth birthday, devoted to Haeckel. For the history of monistic philosophy in general from the Greeks to the present time see "Der Monismus", by various authors, under the editorship of Arthur Drews (Jena: Diederich, 1908) or "Geschichte des Monismus", by Rudolf Eisler (Leipzig: Kröner).
Of the expository and controversial literature, pro and con, it must suffice to mention the following titles: "Die Weltanschauung Haeckel", by Max Upel (Berlin-Schoenberg; Buchverlag der Hilfe), a brief and fairminded critique; "Ernst Haeckel, ein Bild seines Lebens und seiner Arbeit", by Wilhelm Breitenbach (Brackwede i. W.: Verlag von Breitenbach & Hoerster), a tribute to the master on his seventieth birthday; "Haeckel's Welträthsel nach ihren starken und ihren schwachen Seite", by Julius Baumann (Leipzig: Diederich, 1900); "Anti-Haeckel", by F. Loofs, Professor of Theology in Halle; "Philosophia Militans" by F. Paulsen, Professor of Philosophy in Berlin. A good account of the Haeckel-Paulsen controversy by Theodor Lorenz may be found in Deutsche Literaturzeitung, March 12, 1910, and later.
[1] An undergraduate friend of mine to whom I referred these verses for translation into the vernacular of the campus gives me this version:
Who knows the truth and speaks not out
He is indeed a sorry lout!
Who knows the truth and speaks too loose
In Berlin gets in the calaboose!
[2] This is not to be translated, as I once heard a student give it, "Haeckel's one-sided showing-up of the universe."
[3] "Thesen zur Organization des Monism."
[4] "Riddle of the Universe", p. 363.
[5] "Wonders of Life", p. 430.