notion that they may be arrived at through a priori reasoning. For Hume, every effect only follows its cause arbitrarily—they are entirely distinct from one another. (Hume 1974:324) In part two, Hume inquires into how anyone can justifiably believe that experience yields any conclusions about the world: "When it is asked, What is the nature of all our reasonings concerning matter of fact? the proper answer seems to be, that they are founded on the relation of cause and effect. When again it is asked, What is the foundation of all our reasonings and conclusions concerning that relation? it may be replied in one word, experience. But if we still carry on our sifting humor, and ask, What is the foundation of all conclusions from experience? this implies a new question, which may be of more difficult solution and explication." (Hume 1974:328) He shows how a satisfying argument for the validity of experience can be based neither on demonstration (since "it implies no contradiction that the course of nature may change") nor experience (since that would be a circular argument). (Hume 1974:330-332) Here he is describing what would become known as the problem of induction. 5. Sceptical solution of these doubts (in two parts) According to Hume, we assume that experience tells us something about the world because of habit or custom, which human nature forces us to take seriously. This is also, presumably, the "principle" that organizes the connections between ideas. Indeed, one of the many famous passages of the Enquiry is on the topic of the incorrigibility of human custom. In Section XII, Of the academical or sceptical philosophy, Hume will argue, "The great subverter of Pyrrhonism or the excessive principles of skepticism is action, and employment, and the occupations of common life. These principles may flourish and triumph in the schools; where it is, indeed, difficult, if not impossible, to refute them. But as soon as they leave the shade, and by the presence of the real objects, which actuate our passions and sentiments, are put in opposition to the more powerful principles of our nature, they vanish like smoke, and leave the most determined skeptic in the same condition as other mortals." (Hume 1974:425) In the second part, he provides an account of beliefs. He explains that the difference between belief and fiction is that the former produces a certain feeling of confidence which the latter