This long analysis was necessary to show how the real can pass from tension to extension and from freedom to mechanical necessity by way of inversion. It was not enough to prove that this relation between the two terms is suggested to us, at once, by consciousness and by sensible experience. It was necessary to prove that the geometrical order has no need of explanation, being purely and simply the suppression of the inverse order. And, for that, it was indispensable to prove that suppression is always a substitution and is even necessarily conceived as such: it is the requirements of practical life alone that suggest to us here a way of speaking that deceives us both as to what happens in things and as to what is present to our thought. We must now examine more closely the inversion whose consequences we have just described. What, then, is the principle that has only to let go its tension--may we say to _detend_--in order to _extend_, the interruption of the cause here being equivalent to a reversal of the effect? For want of a better word we have called it consciousness. But we do not mean the narrowed consciousness that functions in each of us. Our own consciousness is the consciousness of a certain living being, placed in a certain point of space; and though it does indeed move in the same direction as its principle, it is continually drawn the opposite way, obliged, though it goes forward, to look behind. This retrospective vision is, as we have shown, the natural function of the intellect, and consequently of distinct consciousness. In order that our consciousness shall coincide with something of its principle, it must detach itself from the _already-made_ and attach itself to the _being-made_. It needs that, turning back on itself and twisting on itself, the faculty of _seeing_ should be made to be one with the act of _willing_--a painful effort which we can make suddenly, doing violence to our nature, but cannot sustain more than a few moments. In free action, when we contract our whole being in order to thrust it forward, we have the more or less clear consciousness of motives and of impelling forces, and even, at rare moments, of the becoming by which they are organized into an act: but the pure willing, the current that runs through this matter, communicating life to it, is a thing which we hardly feel, which at most we brush lightly as it passes. Let us try, however, to instal ourselves within it, if only for a moment; even then it is an individual and fragmentary will that we grasp. To get to the principle of all life, as also of all materiality, we must go further still. Is it impossible? No, by no means; the history of philosophy is there to bear witness. There is no durable system that is not, at least in some of its parts, vivified by intuition. Dialectic is necessary to put intuition to the proof, necessary also in order that intuition should break itself up