AN OUTLINE OF THE THEORY. 15 
sprang from the earth by means of germs carried in the 
atmosphere which gave fecundity to the earth. Aristotle 
held opinions not very unlike those of our own day. All 
of which goes to show that speculation about the origin of 
the universe and the why and wherefore of living things 
did not come into existence with the Darwinian hypothesis 
and that the doctrine of descent with modification as an 
explanation of all biological phenomena antedates by over 
two thousand years the publication of the “Origin of Spe- 
cies.” 
In modern times a theory of development was first 
suggested by Goethe in his “Jtalienische Reise.” Acting 
under the same mental urge for seeing diverse forms un- 
der a unifying principle, Goethe looked for the original 
form of plant life, the Urp/lanze, the plant which would 
be at once simple enough to stand for a type of all plants, 
and yet susceptible to variation in so many directions that 
all plants might derive from it their origin. Goethe has 
also clothed this conception in poetic form. 
The first philosophic statement of the hypothesis is 
found in Immanuel Kant’s “Kritik der Urteilskraft,” 1790. 
In paragraph 80 we find a discussion of the similarity be- 
tween so many species of animals, not only in their bony 
structure, but also in the arrangement of their other parts, 
a similarity which, says Kant, “casts a ray of hope,” that 
all forms may be traced back to original simple forms, to 
“a generation from a common ancestor,” rising from the 
lowest forms to man, “according to mechanical laws.’’ 
Kant assumes that, for instance, certain aquatic animals 
by and by formed into amphibia, and from these after 
some generations were produced land animals. A trea- 
tise of the same philosopher entitled “Presumable Origin 
of Humanity” suggests that man in the early age of the 
world was developed from “mere animal creatures.” 
Even a universal law of world-formation (cosmic evolu- 
