A strong writer and thinker, his spirit was essentially unifying and sympathetic, in an age when these qualities won little sympathy.
But the unifying process may advance along different lines.
To secure fairly uniform efficiency in the various corps, and also as a means of unifying Italy, Piedmontese, Umbrians and Neapolitans are mixed in the same corps and sleep in the same barrack room.
This argument was tacitly accepted or explicitly avowed by almost every writer on the theory of geography, and Carl Ritter distinctly recognized and adopted it as the unifying principle of his system.
The evolutionary theory, more than hinted at in Kant's " Physical Geography," has, since the writings of Charles Darwin, become the unifying principle in geography.