It proceeds on the assumption, akin to that of Epicurus, that atoms or monads alone existed in the first instance; and that from these were derived, under the action of natural law and by a process of gradual development, all existing substances and beings, whether organic or inorganic, mineral, vegetable, or animal.

"No organism has been created," says Dr.Oken, "of larger size than an infusorial point.

No organism is, nor ever has one been created, which is not microscopic.

Whatever is larger has not been created, but developed.

Man has not been created, but developed." On this fundamental assumption the whole theory is based.