 This is a problematic passage. The “great propensity” here cited is not the irresistible compulsion of clear and distinct perception. (If it were, the conclusion that sensation is caused by material objects would follow straightaway from this clear and distinct perception, via the C&amp;D Rule.) But unless each step of the argument is clearly and distinctly perceived, Descartes should not be making the argument. Adding to the difficulties of the passage, he expressly cites the conclusion as following from the fact that “God is not a deceiver,” implying that he thinks this inference is supported by a divine guarantee.