Here the famous " problem of induction " arises. Hume argues that this all-important inference cannot be accounted for by any process of reasoning: neither demonstrative reasoning nor probable reasoning. Not demonstrative reasoning: it cannot be demonstrated that the future will resemble the past, for "[w]e can at least conceive a change in the course of nature", in which the future significantly differs from the past. And not probable reasoning: that kind of reasoning itself draws on past experience, which means it presupposes that the future will resemble the past . In other words, in explaining how we draw on past experience to make causal inferences, we cannot appeal to a kind of reasoning that itself draws on past experience—that would be a vicious circle that gets us nowhere.
He settles the issue by showing how various aspects of culture - including 1) motion (which affirms the internal reality of the observer due to the feeling of the sublime that arises from the difference felt between the observer/human and the spectacle/nature, as when seeing the shore from a moving ship), 2) poetry (which affirms the reality of the soul by the way in which poets conform nature to their thoughts and "makes them the words of the Reason" or the soul), 3) philosophy (which like poetry, affirms the reality of the soul by the way in which philosophers animate nature with their thoughts and makes them the words of Reason, except in this case for Truth rather than Beauty), 4) intellectual science (which generates insight based on abstract ideas and thus the spirit), and 5) religion and ethics (which degrades nature and suggests its dependence on the spirit) - convince us of the reality of the external world, of nature and spirit, and thus tend to imbue us with a moderate form of idealism: