Smith goes first to Descartes (and Modernity) for the idea that a human is a thinking thing rather than a being "of the heart." When Descartes famously decides that "I think, therefore I am," the next question should be (according to Smith), "What am I?" But Smith suggests that Descartes has already concluded that this is all, as the physical senses can deceive. Thus, "what nourishes the 'I' is a steady diet of ideas, fed somewhat intravenously into the mind through the lines of propositions and information." (42) And, much to our chagrin, this model was accepted readily by Protestant Christianity (thus the stress on messages one might receive from the world around them, and a latent anti-intellectualism). (42)
These are scathing views of the cognitive centricity of the Protestant Church. He goes on right at the start of the next section to suggest that the Reformed tradition of Protestant Christianity has contested this view as reductionist. If they've got it right, that's good.