I shall venture to quote a hardy passage from another article (_Pyrrhonienne_) which some will think a measure of Diderot's philosophical incompetency, and others will think a measure of his good sense. "We will conclude," he says, "for our part that as all in nature is bound together, there is nothing, properly speaking, of which man has perfect, absolute, and complete knowledge, because for that he would need knowledge of all. Now as all is bound together, it inevitably happens that, from discussion to discussion, he must come to something unknown: then in starting again from this unknown point, we shall be justified in pleading against him the ignorance or the obscurity or the uncertainty of the point preceding, and of that preceding this, and so forth, up to the most evident principle. So we must admit a sort of sobriety in the use of reason. When step by step I have brought a man to some evident proposition, I shall cease to dispute. I will listen no longer to a man who goes on to deny the existence of bodies, the rules of logic, the testimony of the senses, the difference between good and evil, true and false, etc. etc. I will turn my back on everybody who tries to lead me away from a simple question, to embark me in discussion as to the nature of matter, of the understanding of thought, and other subjects shoreless and bottomless."[185] Whatever else may be said of this, we have to recognise that it is exactly characteristic of the author. But then why have written on metaphysics at all?