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?
We have mentioned the article on Spinosa.

It is characteristic both of the good and the bad sides of Diderot's work.

Half of it is merely a reproduction of Bayle's criticisms on Spinosa and his system.