6 THE WORLD AS IDEA.
we consider it at present, has two fundamental, necessary, and inseparable halves. The one half is the object, the forms of which are space and time, and through these multiplicity. The other half is the subject, which is not in space and time, for it is present, entire and undivided, in every percipient being. So that any one percipient being, with the object, constitutes the whole world as idea just as fully as the existing millions could do; but if this one were to disappear, then the whole world as idea would cease to be. These halves are therefore inseparable even for thought, for each of the two has meaning and existence only through and for the other, each appears with the other and vanishes with it They limit each other immediately ; where the object begins the subject ends. The universality of this limitation is shown by the fact tnatthe essential and hence universal forms of all objects, space, time, and causality, may, without knowledge of the object, be discovered and fully known from a consideration of the subject, i.e., in Kantian language, they lie a priori in our consciousness. That he discovered this is one of Kant's principal merits, and it is a great one. I however go beyond this, and maintain that the principle of sufficient reason is the general expression for all these forms of the object of which we are a priori conscious; and that therefore all that we know purely a priori, is merely the content of that principle and what follows from it; in it all our certain a priori knowledge is expressed. In my essay on the principle of sufficient reason I have shown in detail how every possible object comes under it; that is, stands in a necessary relation to other objects, on the one side as determined, on the other side as determining: this is of such wide application, that the whole existence of all objects, so far as they are objects, ideas and nothing more, may be entirely traced to this their necessary relation to each other, rests only in it, is in fact merely relative; but of this more presently. I have further
