This goes without saying, but sometimes wiki pages are created and extended with discussions about this topic with a different subject and a different object. The outcome is always the same.
Ceci n'est pas une pipe.
Alors, qu'estcequec'est une pipe? I mean, what is a real thing if it is not your representation of something you expect others to represent too? Where is this more fundamentally real thing that you represent, except as part of your representation?
Cf. LeibnizianDefinitionOfConsciousness and all that EasternThought claptrap.
See also http://www.tcf.ua.edu/Classes/Jbutler/T340/SurrealismLecture.htm and . . .