same does not here remain the same, but is reinforced and swollen by the whole of its past. In short, while the material point, as mechanics understands it, remains in an eternal present, the past is a reality perhaps for living bodies, and certainly for conscious beings. While past time is neither a gain nor a loss for a system assumed to be conservative, it may be a gain for the living being, and it is indisputably one for the conscious being. Such being the case, is there not much to be said for the hypothesis of a conscious force or free will, which, subject to the action of time and storing up duration, may thereby escape the law of the conservation of energy? [Sidenote: The idea of the universality of conservation depends on confusion between concrete duration and abstract time.] In truth, it is not a wish to meet the requirements of positive science, but rather a psychological mistake which has caused this abstract principle of mechanics to be set up as a universal law. As we are not accustomed to observe ourselves directly, but perceive ourselves through forms borrowed from the external world, we are led to believe that real duration, the duration lived by consciousness, is the same as the duration which glides over the inert atoms without penetrating and altering them. Hence it is that we do not see any absurdity in putting things back in their place after a lapse of time, in supposing the same motives acting afresh on the same persons, and in concluding that these causes would again produce the same effect. That such an hypothesis has no real meaning is what we shall prove later on. For the present let us simply show that, if once we enter upon this path, we are of course led to set up the principle of the conservation of energy as a universal law. For we have thereby got rid of just that difference between the outer and the inner world which a close examination shows to be the main one: we have identified true duration with apparent duration. After this it would be absurd to consider time, even _our_ time, as a cause of gain or loss, as a concrete reality, or a force in its own way. Thus, while we ought only to say (if we kept aloof from all presuppositions concerning free will) that the law of the conservation of energy governs physical phenomena and _may,_ one day, be extended to all phenomena if psychological facts also prove favourable to it, we go far beyond this, and, under the influence of a metaphysical prepossession, we lay down the principle of the conservation of energy as a law which _should_ govern all phenomena whatever, or must be supposed to do so until psychological facts have actually spoken against it. Science, properly so called, has therefore nothing to do with all this. We are simply confronted with a confusion between concrete duration and abstract time, two very different things. In a word, the so-called physical determinism is reducible at bottom