We see therefore that our author agrees with Mr. Herbert Spencer in granting the existence of the absolute; he does not seem to reduce it, as Kant does, to a mere idea. He confines himself to saying that it cannot be determined. He shows that none of the notions that have been previously examined can fill up the concept of the absolute. Neither space, nor time, nor substance, nor cause, nor the totality of phenomena, can be raised to the notion of absolute. It is therefore indeterminable. Now, as the absolute is the proper object of metaphysics, it follows that metaphysics lack an object, having nothing to say thereon. Hence it is self-condemned, and consequently metaphysics is not a science. Such is the conclusion of the second part. The first appeared to raise us above phenomena by establishing the necessity of thought and of its fundamental law. But the second confines us within the domains of thought, and forbids us to go beyond. There is, indeed, a science of thought, but this science is criticism, not metaphysics. Have we, then, only escaped from positivism to fall into the abyss of scepticism? Before explaining in what manner the author has endeavoured to escape from this abyss, there is room for an important remark on the previous discussion as to the notion of the absolute. Scepticism on this point may assume three forms. Either, first, we do not even possess the notion of it, our notion is entirely negative,--the absolute is the non-relative, is indeed the relative with a negation: such is the view of Sir W. Hamilton. Or else, secondly, we have the notion of the absolute, of being in itself and by itself, of the superlatively real being, _ens realissimum_, as Kant expresses it, but it is only a notion, we cannot affirm the existence: this is Kant's doctrine. Or, thirdly, we have indeed a positive notion of the absolute, and we necessarily affirm its existence, only we are unable to determine its nature: this is the conclusion arrived at by Herbert Spencer. Now, of these three doctrines the two first alone, in our opinion, belong to what may be called criticism. The third is manifestly a return to dogmatism. The more or less of determination in the notion of the absolute is only the second problem of metaphysic; the first is the existence of that absolute. And, moreover, the doctrine of the divine incomprehensibility has always been maintained by the greatest metaphysicians as well as the greatest theologians. All mystics incline to it. There may therefore be room for debate as to the more or less approximative character of our concepts of the absolute. That any of these are adequate, or absolutely adequate, is what no philosopher has ever thought himself obliged to maintain. No doubt, to define the absolute as the unknowable, is to express the doctrine under a very rigorous form, but one could hardly refuse to allow the absolute to be the incomprehensible.