The mention of one apartment in a building naturally introduces an enquiry or discourse concerning the others: and if we think of a wound, we can scarcely forbear reflecting on the pain which follows it.
David Hume (1711–1776), Scottish philosopher. Enquiries Concerning the Human Understanding and Concerning the Principles of Morals, sect. 3 ("Of the Association of Ideas"), p. 24, ed. L. Selby-Bigge, M.A., 2nd edition, London, Oxford University Press (1902).
On the association of ideas, from "An Enquiry Concerning Human Understanding."