Fourthly: “The determinateness and the variation thereby established is, however, an inward implicit principle; it is a multiplicity of modifications, of relations to surrounding existences, but a multiplicity which remains locked up in simplicity. Determinateness and variation such as this, which remains and goes on in the existence itself, is a perception;” and therefore Leibnitz says all monads perceive or represent (for we may translate _perceptio_ by representation [Vorstellung]). In other words, they are in themselves universal, for universality is just simplicity in multiplicity, and therefore a simplicity which is at the same time change and motion of multiplicity. This is a very important determination; in substance itself there is negativity, determinateness, without its simplicity and its implicitude being given up. Further, in it there is this idealism, that the simple is something in itself distinguished, and in spite of its variation, that it yet remains one, and continues in its simplicity. An instance of this is found in “I,” my spirit. I have many conceptions, a wealth of thought is in me, and yet I remain one, notwithstanding this variety of state. This identity may be found in the fact that what is different is at the same time abrogated, and is determined as one; the monads are therefore distinguished by modifications in themselves, but not by external determinations. These determinations contained in the monads exist in them in ideal fashion; this ideality in the monad is in itself a whole, so that these differences are only representations and ideas. This absolute difference is what is termed the Notion; what falls asunder in the mere representation is held together. This is what possesses interest in Leibnitz’s philosophy. Such ideality in the same way pertains to the material, which is also a multiplicity of monads; therefore the system of Leibnitz is an intellectual system, in accordance with which all that is material has powers of representation and perception. As thus representing, the monad, says Leibnitz, possesses activity; for activity is to be different, and yet to be one, and this is the only true difference. The monad not only represents, it also changes; but in doing so, it yet remains in itself absolutely what it is. This variation is based on activity. “The activity of the inner principle, by means of which it passes from one perception to another, is desire (_appetitus_).” Variation in representation is desire, and that constitutes the spontaneity of the monad; all is now complete in itself, and the category of influence falls away. Indeed, this intellectuality of all things is a great thought on the part of Leibnitz: “All multiplicity is included in unity;”[251] determination is not a difference in respect of something else, but reflected into itself, and maintaining itself. This is one aspect of things, but the matter is not therein complete; it is equally