It is obvious that we do not attempt to conceal the very grave difficulties which the solution of this problem offers: on the contrary, we point them out with all clearness, in order to avoid that vain presumption which is as fatal to science as to every thing else. But let it not be supposed that we intend to banish this question from the arena of philosophy: for many and serious as are its difficulties, we are yet of opinion that they allow of sufficiently probable conjectures. 112. The representative force may emanate from any one of these three sources: identity, causality, or ideality. We will explain ourselves. A thing may represent itself; and this we call representation of identity. A cause may represent its effect; and this is what we understand by representation of causality. A being, whether substance or accident, may represent another distinct from itself, which is not its effect; and this we call representation of ideality. We do not see how it is possible to assign any other source of representation: holding, therefore, the division to be complete, we will examine its three points; and we beg to call the attention of the reader more especially to this matter, because it is one of the most important in philosophy. 113. That which represents must have some relation to the thing represented: whether essential or accidental, inherent or communicated, this relation must exist. Two beings, having absolutely no relation, one of which nevertheless represents the other, are a monstrosity. There is nothing without a sufficient reason; and there being no relation between the thing representing, and that represented, there is no sufficient reason of the representation. It is here to be borne in mind that, for the present, we abstract the nature of this relation; we do not assert it to be either real or ideal; we only say that, between the thing representing and that represented, there must be some link, whatever that link may be. Its mysteries, its incomprehensibility, do not destroy its existence. Philosophy perhaps may be unable to explain the enigma; but it can demonstrate the existence of the link. Thus, abstracting all experience, it is possible to demonstrate _a priori_, that there is a relation between the _me_ and other beings, by the mere fact of their representation existing in the _me_. The incessant communication of intelligences with each other, and with the universe, proves that there is a point of union for them all. Representation, alone, is a convincing proof of this: so many beings, apparently dispersed and unconnected, are intimately united in some centre, so that the simple phenomenon of intelligence leads us to affirm the common link, the unity in which plurality is joined. This unity, with pantheists, is universal identity; with us, it is God.