Full Idea
Is it really an issue whether things are true that appear to those asleep or to those awake? No one in Libya who dreamt he was in Athens, would set out for the Odeon next morning!
Gist of Idea
Dreams aren't a serious problem. No one starts walking round Athens next morning, having dreamt that they were there!
Source
Aristotle (Metaphysics [c.324 BCE], 1010b09)
Book Reference
Aristotle: 'Metaphysics', ed/tr. Lawson-Tancred,Hugh [Penguin 1998], p.102