in any system of classification they must find a place along with living animals.
Although he had distinctly before him the idea of a succession of faunas upon the earth, yet he refused to admit the speculative or philosophical conclusions which were arrived at by his contemporaries Lamarck and Saint-Hilaire. He firmly stuck to the doctrines of the immutability of species and successive cataclysms. Subsequent events have proved that this was a misfortune, for Cuvier was one of "the most remarkable intelligences of his own or any time."
Although Saint-Hilaire and Cuvier were bosom friends in their youth, their ideas gradually diverged as years rolled on, culminating in 1830 "in the most famous of all scientific duels." Cuvier was a strict, matter-of-fact man, and could not tolerate the vagaries of the Naturphilosophie school; but in later years he allowed his scientific imagination to run wild by enunciating the doctrines of (1) fixity of species; (2) emboîtement in embryology; (3) physiological deduction as the basis of palæontology; (4) the restriction of natural history to observation and classification; and (5) the successive cataclysms. All these doctrines, and especially the first and last, were destined to be overthrown:—
It must be so, for miracles are ceased;
And therefore we must needs admit the means
How things are perfected.
Shakespeare.
