Thus we see, that although infinite divisibility and infinite extension are common to both Time and Space, these two forms of empirical representations differ fundamentally, inasmuch as what is essential to the _one_ is without any meaning at all for the _other_: juxtaposition having no meaning in Time, succession no meaning in Space. The empirical representations which belong to the orderly complex of reality, appear notwithstanding in both forms together; nay, the _intimate union_ of both is the condition of reality which, in a sense, grows out of them, as a product grows out of its factors. Now it is the Understanding which, by means of its own peculiar function, brings about this _union_ and connects these heterogeneous forms in such a manner, that _empirical reality_--albeit only for that Understanding--arises out of their mutual interpenetration, and arises as a collective representation, forming a complex, held together by the forms of the principle of sufficient reason, but whose limits are problematical. Each single representation belonging to this class is a part of this complex, each one taking its place in it according to laws known to us _à priori_; in it therefore countless objects _coexist_, because Substance, _i.e._ Matter, remains permanent in spite of the ceaseless flow of Time, and because its states change in spite of the rigid immobility of Space. In this complex, in short, the whole objective, real world exists for us. The reader who may be interested in this, will find the present rough sketch of the analysis of empirical reality further worked out in § 4 of the first volume of "Die Welt als Wille und Vorstellung,"[55] where a closer explanation is given of the way in which the Understanding effects this union and thus creates for itself the empirical world. He will also find a very important help in the table, "_Prædicabilia à priori_ of Time, Space, and Matter," which is added to the fourth chapter of the second volume of the same work, and which I recommend to his attention, as it especially shows how the contrasts of Time and Space are equally balanced in Matter, as their product, under the form of Causality. [55] Vol. i. p. 12, and _seqq._ of the 1st edition; p. 9 of the 3rd edition. We shall now proceed to give a detailed exposition of that function of the Understanding which is the basis of empirical reality; only we must first, by a few incidental explanations, remove the more immediate objections which the fundamental idealism of the view I have adopted might encounter. § 19. _Immediate Presence of Representations._