Thus the decade between 1745 and 1755 was marked by the appearance of the attack of Maupertuis upon the ruling doctrine of predelineation; by the publication of the volumes of the 'Histoire Naturelle' which familiarized even the general reader with the unity of type and the homologies of structure that ran through the most diverse species in the writings of the three most celebrated French leaders of scientific opinion of the time; and by the setting forth of two distinct lines of argument in favor of that hypothesis. From this decade, then, dates the appearance of modern evolutionism, as a theory definitely formulated and based upon its proper embryological and anatomical premises.
III. Herder.—If certain of the French philosophes have received less credit than is their due for their evolutionary opinions, Herder, on the contrary, has often been praised for an early profession of faith in the doctrine of the transformation of species, whereas it is by no means clear that he did not intend explicitly to repudiate it. A German writer, Bärenbach, has written a book to show that Herder was a precursor of Darwin, and declares that in his 'Ideen zur Geschichte der Menschheit' Herder laid down 'the fundamental laws of the modern development theory, and of the Darwinian theory in particular,' and that he gave clear expression to 'The law of the evolution of organisms, and the theories of the struggle for existence and of natural selection.' Professor Osborn's account of Herder's relation to the theory apparently follows Barenbach, and as a result is rather misleading. Herder, says Osborn, probably was helped to his evolutionism by 'coming under the influence of Kant's earlier views.' But "Herder was less cautious than his master, and appears almost as a literal prophet of the modern natural philosophy. In a general way he upholds the doctrine of the transformation of the lower and higher forms of life, of a continuous transformation from lower to higher types and of the law of perfectibility. " "In his 'Ideen,' published in Tübingen in 1806, . . . we see that Herder clearly formulated the doctrine of unity of type which prevailed among all the evolutionists of the period immediately following."
These few sentences contain a rather undue proportion of errors, and the whole exposition of Herder's position from which they are taken is substantially wrong. It is worth while, therefore, to attempt a more accurate account of Herder's attitude towards evolutionism than is to be found in the current writings on the subject. In a matter of this kind, even accuracy about dates is not wholly to be disdained; and it should be observed that the 'Ideen' were published, not at Tübingen in 1806, but at Riga and Leipzig in 1784-5. Again, Herder, although once a pupil, was no disciple of Kant's; the author of the
- Herder als Vorgänger Darwin's; cf. the same writer's monograph on Herder in 'Der neue Plutarch, VI.' My citation is from the latter work; the former is not accessible to me.