I know that joke too.
Still not a paradox-merely an untruth.
Yes, in the real world it’s a picture of a pipe. But the message is also inside the picture, and in that universe the object in question really is a pipe.
But not a penis.
I suppose the appropriate audio clip would be Elton’s:
If I asked your neighbor here what your answer would be, what would he say?
Whatever he says, do the opposite.
I was going to tell you about paralipsis, but changed my mind.
Allow me to clarify:
Performatives.
Thanks - I knew it was something like that, but you know when you just have a mental block on some piece of information for some reason?
In that case, I think the term the OP was looking for is performative contradiction, whose meaning is fairly obvious, but I can’t find a really good online cite.