104 THEOLOGIANS AND NATURAL PHILOSOPHERS. 



Similarities of external and, still more, of internal, structure per- 

 vade all the land animals and are repeated in man. The am- 

 phibia, birds, fishes, insects, water animals, depart in widening 

 degrees from this main type, which is lost in the plant and inor- 

 ganic creation. Our vision reaches no further, but all these trans- 

 fers render it not improbable that in the series of extinct forms 

 the same type, in a ruder and simpler form, may have prevailed. 

 We can, therefore, assume that, according to their nearness to 

 man, all beings have their greater or less likeness to him, and that 

 the nature of all Hfe seems to conform to a main single plasticity 

 of organization." 



We see here that Herder clearly formulated the 

 doctrine of unity of type, which prevailed among all 

 the evolutionists of the period immediately following. 



Friedrich Wilhelm Joseph Schelling (1775— 

 1854) at the age of twenty published his Ideen zur 

 einer Philosophie der Natur. Here he first unfolded 

 his ideas of the Philosophy of Nature, Kant having 

 spoken of the science of Nature. One section of 

 his philosophy was followed and developed by Oken, 

 but Schelling was greatly admired also by Kiel- 

 meyer, and undoubtedly exercised great influence 

 upon Goethe. Isidore St. Hilaire pays him a high 

 tribute, and speaks at length of the admiration felt 

 for Schelling in France ; he places him midway 

 between the general philosopher, typified by the 

 more metaphysical writers, and the philosopher of 

 natural objects, such as Geoffroy St. Hilaire. 

 Schelling independently arrived at the conclusion 

 of Kielmeyer, that all the functions of life are but 

 the diverse modifications of a single force. 



