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Rádl, Emanuel


(b. Pysely, Bohemia [now Czechoslovakia], 21 December 1873; d. Prague, Czechoslovakia, 12 May 1942)

philosophy, history of biological sciences.

Rádl was one of the eleven children of Frantǐek Rádl, a poor peddler, and his wife, Barbara. Of six children who survived infancy, one brother became professor of mathematics at Prague Technical University, and Rádl himself was mathematically gifted. With the help of an uncle, who was an abbot, Rádl graduated from the Gymnasium in Domǎlice, then entered a seminary to study theology. He gave up this study after some time, however, over the objections of his parents, and went to Prague, where he worked his way through the university, supporting himself by tutoring. He was a brilliant student and took the Ph.D. in natural sciences. While at the university Rádl was influenced by F. Vejdovsky, a leading zoologist, and, especially, T. G. Masaryk, who was then a professor of philosophy. During his last years as a student Rádl began to publish scientific papers; the first, in 1897, was a petrological study, while later works were concerned with biology.

Since no teaching posts were available at the University of Prague, Rádl was obliged to take the state education examinations and to accept a post at a secondary school in Pardubice, in eastern Bohemia. With the limited means at his disposal, Rádl continued to work enthusiastically in biology, the history of biology, comparative psychology, and philosophy. In 1904 he qualified as Privatdozent at the University of Prague, assigned to teach the biology of invertebrates “with special regard to its historical development.” The post was unsalaried, and Rádl simultaneously taught at a secondary school in Prague; his connection with the university, however, allowed him access to its extensive library, and he continued his own studies, working day and night.

Rádl published steadily, in both Czech and German, on a wide variety of topics. Most of his papers written during this period were summarized in Untersuchungen ̈ber den Phototropismus der Tiere (1903) and Neue Lehre vom zentralen Nervemystem (1913). Even more important than his biological articles were his critical essays on such topics as the philosophy of naturalists, Czech Naturphilosophen, Goethe, Leibniz and Stahl, vitalism, and the mechanics of evolution. Chief among these was his study (1900) of the histological work of the Czech biologist Purkyn̈e, in which Rádl attempted to analyze Purkyne’s method and genius.

With the publication of Geschichte der biologischen Theorien (1905–1909) Rádl’s name became widely known. The work is by no means an ordinary textbook, and Rádl’s conception of the history of biology is still thought-provoking. His reputation, gained largely from this book, earned him a place on the editorial board of Isis, at its founding in 1913, and the first issue contains his article on Paracelsus.

World War I ended this international cooperation and increased the difficulty of Rádl’s life in Prague, since he was known as a disciple of Masaryk, who was then in political exile. With the help of Masaryk, who became the first president of the Czechoslovak Republic in 1918, Rádl was appointed professor of philosophy and history of natural sciences at Prague. The war had changed Rádl’s outlook, however, and he began to work toward a synthesis of philosophy and socially responsible religion. He traveled widely, disseminating his ideas, and took part in several international conferences. His chief concerns were reflected in Zdpad a Vychod(“West and East,” 1925), in which he proposed a nonformalized western Christianity as a unifying philosophy.

In 1907 Rádl, again with the encouragement of his uncle, married Marie Ptacnikova, the convent-educated daughter of a rich notary in Domazlice. His financial condition improved, but his domestic life was not always harmonious; his wife was a strongly conservative Catholic, while Rádl had left that church to become a liberal Protestant. When Rádl was invited to join the faculty of an American university during his travels around the world in 1921–1922, his wife refused to accompany him and he returned to Prague, where he devoted himself to his philosophical work.

Rádl worked to propagate Masaryk’s social and philosophical ideals; he was himself, in fact, the more profound philosopher. During this time he also wrote a Czech textbook for his students, Moderní v̌da (“Modern Science,” 1926), and applied his general erudition to the organization of the new Masaryk encyclopedia. Rádl’s two-volume Ďjiny filosofie (“History of Philosophy,” 1932–1933) considered philosophers of all periods and reflected Rádl’s view that they should accept personal responsibility to work for the good of mankind. In addition he wrote books on the political problems that had begun to concern not only Czechoslovakia but also the world; these included V̓ltka ̌ech̊ s Ňmci (’The War of the Czechs Against the Germans,” 1928), also published in German as Der Kampf zwischen Tschechen und Deutschen, and O nemecke revoluci (“On the German Revolution,” 1933).

Rádl wrote on the contemporary mission of philosophy in such books as N̓bǒenstvi a politika (“Religion and Politics,” 1921); this was also the chief concern of the Eighth International Congress of Philosophy held at Prague in 1934, of which Rádl was organizer and president. These activities, together with increasing political tensions, limited the time and attention that Rádl was able to devote to the history of science; he initiated a collaboration with Otakar Matoǔek, who later succeeded him at the university, to write a major work on this subject.

This project was not realized; in 1935 Rádl suffered a light stroke, which was followed by another in the next year. He recovered from these, but was soon afterward ordered to stay at home, where he spent the last five years of his life as an invalid, increasingly removed—through his wife’s unhappy anxiety—from the world, from his friends, and often even from his own children. He continued to write, and his study “La philosophie de T. G. Masaryk” appeared in 1938; in 1939 he published V̌da a vira u Komenského (“On the Science and Faith of Comenius,” 1939), the last work that he himself was to see in print. The Nazi occupation of Czechoslovakia made further publication impossible. He died unexpectedly of pneumonia in the room to which he had been confined for five years. He left a penciled manuscript, Útěcha z filosofie (“Consolation from Philosophy”), which, although unpublishable during World War II, went through three editions after the war ended, prior to 1948. A fourth edition was published in 1968.

The predominant factor of Rádl’s philosophy was idealism. Although he was influenced by Marx and by the Russian Revolution of 1917, he opposed materialism and asked for a deeper understanding of the human soul; he thus earned enemies on both sides. The “Consolation” is valuable chiefly as an illustration of his own spirit rather than as a general philosophical program, and as such it is an impressive legacy. He wished to halt the disintegration that he saw in human society, and he saw in philosophy an effective means for doing so; finding most philosophy to be without creative force, he criticized it, embracing a strong practical Christianity.

No complete study of Rádl has yet been made. Journals and newspapers printed articles on some aspects of his life and work in honor of his sixtieth birthday, but not even a eulogy was permitted at the time of his death—indeed, none was given at his funeral. His library was dispersed, and no really complete bibliography of his work survives. Only the first half of Rádl’s career is known outside Czechoslovakia; his work awaits the reediting and translation that will establish him as what he was—one of the most original historians of biological ideas and one of the most original philosophers of his time.


I. Original Works. Rádl’s writings, which dealt with scientific, political, social, and moral problems, were often written in both Czech and German. Many of his works appeared in Sitzungsherichte der K. Böhmischen Gesell-schaft der Wissenschaften, also known as Věstnik K. České společnosti nauk and hereafter cited as Sitzungsberichte. The following is a representative list of his published writings: “Gabbro ze Studéneho v okoli Jilovském” (“Gabbro from Studená in the Vicinity of Jilové”), in Sitzungsberichte (1897), no. 24; “Sur quelques éléments des ganglions optiques chez les décapodes,” in Archives d’anatomie microscopique, 2 (1898), 373–418; “Über den Bau und die Bedeutung der Nervekreuzungen im tractus opticus der Arthropoden,” in Sitzungsberichte (1899), no. 23; “Über die Krümmung der zusammengesetzen Arthro-podenaugen,” in Zoologischer Anzeiger, 23 (1900), 372–379; “J. E. Purkyně práce histologické” (“Purkyně’s Histological Works”), in Sitzungsberichte (1900), no. 15; “O dnešni filosofii přírodní” (“On Contemporary Naturalistic Philosophy”), in Česká mysl, 2 (1901), 206–211, 281–285, 362–366, 437–439; “Untersuchungen über die Lichtreactionen der Arthropoden,” in Archiv für diegesamte physiologie, 87 (1901), 418–466; O morfologickém uýznamu dvojitých oči u členovců (“On the Morphological Characher of the Double Eyes of Arthropoda” Prague, 1901); “Über den phototropismus einiger Arthropoden,”in Biologisches Zentralblatt, 21 (1901), 75–86; and “Über die Bedeutung des Prinzips von der Korrelation in der Biologie,” ibid., 401–416, 490–496, 530–560, 605–621.

subsequent works include “Über specifische Strukturen der nervösen Centralorgane,” in Zeitschrift für wissenschaftliche Zoologie,72 (1902), 31–99; “Bemerkungen Zu den Vorschlägen von R. Pick, die wissenschaftliche Sprachverwirrung betreffend,” in Anatomischer Anzeiger, 21 (1902), 27–29; “Nová pozorování o fototroposmu Zvířat” (“New Observations on Phototropism in Animals”), in Sitzungsberichte (1902), no. 55;Untersuchungen über den Phototropismus der Tiere (Leipzig, 1903); “O vitalismu” (“On Vitalism”), in Česká mysl,5 (1904), 133–137, 206–210; “Über die Anziehung der Organismen durch das Licht,” in Flora oder allgemeine botanische Zeitung, 93 (1904), 167–178; Geschichte der biologischen Theorien seit dem Ende des siebzehnten Jahrhunderts, 2 pts. (Leipzig,1905–1909), 2nd ed., extensively revised, Geschichte der biologischen Theorien in der Neuzeit, Pt. 1(Leipzig-Berlin, (1913); trans. of pt. 2 by E. J. Hatfield, as The History of Biological Theories(London, 1930); “Über das Gehör des Insekten,” in Biologisches Zentralblatt, 25 (1905), 1–5; “Über ein neues Sinnesorgan auf dem Kopfe der Corethralarve,” in Zoologischer Anzeiger, 30 (1906), 169–170; “Einige Bemerkungen und Beobachtungen über den Phototropisums der Tiere,” in Biologisches Zentralblatt, 26 (1906), 677–690; Dějiny vývojových theorii v biologiiXIX. stoleti (“History of Biological Theories in the Nineteenth Century” Prague, 1909); “Über spezifisch differenzierte Leitungsbahnen,” in Anatomischer Anzeiger, 36 (1910), 385–401; Neue Lehre vom zentralen Nervensystem (Leipzig,1913); “Paracelsus. Eine Skizze seines Lebens.” in lsis, 1 (1913), 62–94; and Zur Geschichte der Biologie von Linné bis Darwin (Leipzig, 1915).

Rádl resumed Publishing after World War I with Romantická věda (“Romantic Science,” Prague, 1918)followed by Demokracie a véda(“Democracy and Science” Prague, 1919); T.G. Masaryk (Prague, 1919), with many reprints and translations; Národ a stát (“The Nation and the State” Prague, 1921); Dějiny filosofie (“History of Philosophy”), 2 vols. (Prague, 1932–1933); and Actes du huitiéme congrès international de Philosophie à Prague… 1934 (Prague, 1936), of which Rádl was editor.

II. Secondary Literature. On Rádl’s life and work, see B. Kountník, Emanuel Rádl (Prague, 1933); and J. L Hromádka, Don Quijote české filosofie: E. Rádl, 1873–1942 (“Don Quixote of Czech Philosophy…” New York, 1943).

Otakar MatouŠek

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