The doctrine of non-existence and of illusion is entirely incomprehensible, in the sense in which to comprehend signifies to have a clear idea, and one capable of being directly apprehended. But, if one follows the chain of ideas as logically unrolled, in the way that a mathematician follows the transformations of an algebraical formula, without considering its real contents, it is easy to account for the origin of this theory. If the human mind has no rule superior to itself, if it is the absolute mind, God, all its thoughts are equally true, since we cannot point out error without having recourse to a rule of truth. If all doctrines are equally true, propositions directly and absolutely contradictory are equally true. If all is true, there is no truth; for truth is not conceived except in opposition to at least possible error. If there is no truth, the human reason, which seeks truth by a natural impulse belonging to its very essence, as the magnetized needle seeks the pole,--reason, I say, is a chimera. The truth which reason seeks is an exact relation of human thought to the reality of the world. If the search for this relation is chimerical, the two terms, mind, and the world, may be illusions. A fugitive illusion in presence of an infinite illusion: there is all. You see that these thoughts hang together with rigorous precision. The darkness is becoming visible to us, or, in other words, we are acquiring a perfect understanding of the origin and developments of the absurdity. Put God aside, the law of our will, the warrant of our thought; deify human nature; and a fatal current will run you aground twice over--on the shores of moral absurdity, and on those of intellectual absurdity. These sad shipwrecks are set before our eyes in striking examples; it has been easy to indicate their cause.