[14] _Proceedings_ of the Aristotelian Society (1900-1901), p. 110. [15] _Mind_, New Series, xiii. p. 523; cf. 204, 350. [16] The most striking statement of this argument is to be found in Boutroux's treatise _De la contingence des lois de la nature_, first published in 1874 and reprinted without alteration in 1905. The same general line of thought underlies James Ward's _Naturalism and Agnosticism_ (2nd ed., 1903), and A. J. Balfour's _Foundations of Belief_ (8th ed., 1901). H. Bergson's works on the other hand contain the elements of a reconstruction similar in spirit to the suggestions of the present article. IDELER, CHRISTIAN LUDWIG (1766-1846), German chronologist and astronomer, was born near Perleberg on the 21st of September 1766. After holding various official posts under the Prussian government he became professor at the university of Berlin in 1821, and eighteen years later foreign member of the Institute of France. From 1816 to 1822 he was tutor to the young princes William Frederick and Charles. He died in Berlin on the 10th of August 1846. He devoted his life chiefly to the examination of ancient systems of chronology. In 1825-1826 he published his great work, _Handbuch der mathematischen und technischen Chronologie_ (2 vols.; 2nd ed., 1883), re-edited as _Lehrbuch der Chronologie_ (1831); a supplementary volume, _Die Zeitrechnung der Chinesen_, appeared in 1839. Beside these important works he wrote also _Untersuchungen über d. Ursprung und d. Bedeutung d. Sternnamen_ (1809) and _Über d. Ursprung d. Thierkreises_ (1838). With Nolte he published handbooks on English and French language and literature. His son, JULIUS LUDWIG IDELER (1809-1842), wrote _Meteorologia veterum Graecorum et Romanorum_ (1832).