That, to which the philosopher holds, and from which he promises to explain all that is to be explained, is the consciousness, the subject. This subject he will, therefore, have to comprehend free from all representation of being, in order first to show up in it the ground of all being—of course, for itself. But if he abstracts from all being of and for the subject, nothing pertains to it but an acting. Particularly in relation to being is it the acting. The philosopher will, therefore, have to comprehend it in its acting, and from this point the aforementioned double series will first arise. The fundamental assertion of the philosopher, as such, is this: as soon as the Ego is for itself, there necessarily arises for it at the same time an external being; the ground of the latter lies in the former; the latter is conditioned by the former. Self-consciousness and consciousness of a Something which is not that Self, is necessarily united; but the former is the conditioning and the latter the conditioned. To prove this assertion—not, perhaps, by argumentation, as valid for a system of a being in itself, but by observation of the original proceeding of reason, as valid for reason—the philosopher will have to show, firstly, how the Ego is and becomes for itself; and secondly, that this its own being for itself is not possible, unless at the same time there arises for it an external being, which is not it. The first question, therefore, would be: how is the Ego for itself? and the first postulate: think thyself! construe the conception of thyself, and observe how thou proceedest in this construction. The philosopher affirms that every one who will but do so, must necessarily discover that in the thinking of that conception, his activity, as intelligence, returns into itself, makes itself its own object. If this is correct and admitted, the manner of the construction of the Ego, the manner of its being for itself, (and we never speak of another being,) is known; and the philosopher may then proceed to prove that this act is not possible without another act, whereby there arises for the Ego an external being. It is thus, indeed, that the Science of Knowledge proceeds. Let us now consider with what justice it so proceeds. IV. First of all: what in the described act belongs to the philosopher, as philosopher, and what belongs to the Ego he is to observe? To the Ego nothing but the return to itself; everything else to the description of the philosopher, for whom, as mere fact, the system of all experience, which in its genesis the Ego is now to produce under his observation, has already existence.