Look at that magnificently colored carnation. You see the whole flower, and yet you do not see all of it. You do not see its scent nor its weight. In the human language "whole" means a relative whole, which is at the same time a part. Every particle of the universe is such a dual thing. But in the language of the gods, which is spoken by philosophy, only the absolute universe is whole. When the subject under discussion is not the intellect, but some other part of the world, for instance the eyes, the universal concept of the absolute is not so important, because the faculty of seeing, like the faculty of wealth, is in little danger of being metaphysically abused. One knows that eyes which can see around a corner, or through a block of iron, or which can perceive the scent of a carnation, are as meaningless as a white sorrel. Even though our eyes cannot see the invisible, that does not prevent them from being a universal instrument which can see everything, that is everything visible. If you understand this, you will also see through the miserable wisdom of the professors which wallows on its belly in the dust and cries with the faithful: O Lord, O Lord! similarly to Du Bois-Reymond, who cries out: _Ignorabimus_! It is true that the human mind is an ignoramus in the sense that it is ever learning, because there is inexhaustible material in nature. There is also something unknowable in every particle of nature, just as there is something invisible in every carnation. But the unknowable in the sense used by those ignorant people who cannot understand the human mind because they have a transcendental monster in their mind, such a monstrous unknowable exists only in the imagination of the idolators to whom the true spirit reveals itself as little as the spirit of truth. Just as surely as we know that there cannot be in heaven any knife without a blade and a handle, nor any black horses that are white, just so surely do we know that the faculty of understanding can never and nowhere be the absolute, but must always be a special faculty. The concept of understanding, like the concept of a knife, is limited to a definite instrument. There may be all kinds of knives and intellects, but nothing exists that has escaped from its own skin or from the limitation of its own particular concept. By this standard you may measure the silly thought of those who speak transcendentally of an unlimited faculty of understanding. They haven't any right idea of the mind nor of the universe, of the conceivable nor of the inconceivable, otherwise they would not speak in such a nonsensical sense of the "Limits of Understanding." In short, you see that the relative limitation or absoluteness of reason can only be understood by means of the concept of the absolute. TWENTY-FIRST LETTER