 In La Vérité des sciences contre les sceptiques et les phyrroniens, the tone changed again. Skepticism was no longer condemned as a seed of heterodoxy but only in so far as it discourages men from the practice of mathematical sciences. The skeptical character is obstinate, but he is no atheist nor heretic in the disguise (see Descotes, in VS, Introduction), and in the first part of the book, his arguments against the alchemist’s dogmatism are often endorsed and even reinforced by the Christian philosopher.