Full Idea
Men instinctively suppose the very images presented by the senses to be the external objects, and never entertain any suspicion that the one is nothing but representations of the other.
Gist of Idea
It never occurs to people that they only experience representations, not the real objects
Source
David Hume (Enquiry Conc Human Understanding [1748], XII.I.117)
Book Reference
Hume,David: 'Enquiries Conc. Human Understanding, Morals', ed/tr. Selby-Bigge/Nidditch [OUP 1975], p.151