Karl Christian Planck

[1] In 1850–1851, he published his great book, Die Weltalter, in which he developed a complete original system of philosophy, based on the realistic view that thought should proceed from nature to the highest forms of existence in the spiritual life.

Not only did Planck oppose the idealism of his confreres; his views were, in another aspect, directly antagonistic to the Darwinian theory of descent, which he specifically attacked in Wahrheit und Flachheit des Darwinismus (Nördlingen, 1872).

[1] The natural consequence of this individuality of opinion was that his books were practically disregarded, and Planck was deeply incensed.

The ill success of Die Weltalter nerved him to new efforts, and he repeated his views in Katechismus des Rechts (1852), Grundlinien einer Wissenschaft der Natur (1864), Seele und Geist (1871), and numerous other books, which, however, met with no better fate.

Planck's views were elaborately developed, but his method of exposition told heavily against their acceptance.