The Problem of Induction and Theory-Ladenness of Observation

David Hume, in Book I of A Treatise of Human Nature (1739–1740) and again in the more accessible An Enquiry Concerning Human Understanding (1748), posed what has become known as the problem of induction: our belief that the future will resemble the past, that unobserved instances will conform to the pattern of observed ones — for instance, that bread will continue to nourish us because it has done so before, or that the sun will rise tomorrow because it always has — cannot itself be justified either by demonstrative (deductive) reasoning, since its denial involves no logical contradiction, nor by reasoning from experience, since any such justification would presuppose the very principle of the uniformity of nature that is in question, generating a vicious circularity. Hume's own psychological, rather than logical, resolution attributed our inductive expectations to custom or habit, an associative mechanism of the mind formed through the constant conjunction of similar experiences, rather than to any rationally demonstrable inference — a deflationary account that left the normative justification of induction, as a rational warrant for belief, unresolved in Hume's own terms.