Leibniz, on the other hand, regarded his monad as the ultimate element of everything.
That in it first and in it alone this condition is realized - the individual soul must be held to be an ultimate reality reflecting in its inmost nature, like the monad of Leibniz, the complete fulness and harmony of the whole.
Seit Leibniz (1873, ed.
Probleme in dem Briefwechsel Leibniz and Clarke, Giessen, 1893).
The System der Logik (1828) of Bachmann (a Kantian logician of distinction) contains a historical survey (pp. 569-644), as does the Denklehre (1822) of van Calker (allied in thought to Fries), pp. 12 sqq.; Eberstein's Geschichte der Logik and Metaphysik bei den Deutschen von Leibniz bis auf gegenwartige Zeit (latest edition, 1 799) is still of importance in regard to logicians of the school of Wolff and the origines of Kant's logical thought.
There the vision of a reunion with the Protestants had haunted many Catholic brains ever since Bossuet and Leibniz had corresponded on the subject.