The Common Sense Theory of Theory in the Enquiries, Essays and History of England

While Hume was writing the practical philosophy of the Essays, he was re-thinking the speculative philosophy of the Treatise. In the process of presenting arguments for a popular audience, he must have realized that he could establish the same speculative points using different arguments and that he could make certain points directly, without needing recourse to an elaborate theory of human nature. InAn Enquiry Concerning Human Understanding (the first Enquiry) and An Enquiry Concerning the Principles of Morals (the second Enquiry), Hume re-cast elements of his theory of human nature from the Treatise. As noted earlier, Hume claimed that his changes were more in the manner of presentation, than in the matter or substance of his theory of human nature. One stylistic change, as we will see, is the attempt to combine speculative and practical philosophy by applying the “easy and obvious” style of practical philosophy to the “abstruse” topics of speculative philosophy. But we also noted a number of substantive changes and omissions between the Treatise and the later Enquiries. What drops out is the naturalist system of the Treatise. What replaces it are some of the skeptical elements of Book 1 of the Treatise which are used (as they were in the Treatise) to demolish religious and metaphysical theories, and result in a conception of philosophy as “nothing but reflections of common life, methodized and corrected.”