still inform you, that there had secretly revolv'd in his Mind a Succession of Thought, which had gradually led him away from the Subject of Conversation. Amongst the Languages of different Nations, even where we cannot suspect the least Connexion or Communication, 'tis found, that the Words, expressive of the most compound Ideas, do yet nearly correspond to each other: A certain Proof, that the simple Ideas, which they express, were bound together by some universal Principle, which had an equal Influence on all Mankind.
Tho' it be too obvious to escape our Observation, that different Ideas are connected together; I do not find, that any Philosopher has attempted to enumerate or class all the Principles of Connexion; a Subject, however, that seems very worthy of our Curiosity. To me, there appears to be only three Principles of Connexion among Ideas, viz. Resemblance, Contiguity in Time or Place, and Cause or Effect.
That these Principles serve to connect Ideas will not, I believe, be much doubted. A Picture naturally leads our Thoughts to the Original[1]: The Mention of one Apartment in a Building naturally introduces an Enquiry or Discourse concerning the others[2]: And ifwe
