But I assert it is trivial to specify a square that is perfectly circular and is yet still a square.
Doesn't that undo your illustration?
You do concur it is possible to specify a square that is perfectly circular and is yet still a square, don't you?
Intrinsic:
1. basic and essential: belonging to something as one of the basic and essential elements that make it what it is
2. of itself: by or in itself, rather than because of its associations or consequences
3. ANATOMY found in body part: occurring wholly within or belonging wholly to a part of the body, for example, an organ
Do you two really not understand the point?
It's not a trivial question. Assuming that the words "circle" and "square" have a specific meaning, what is propposed (a circular square) is this: Can there be an "A" which is also -- at the same time -- not an "A". So the question becomes this: Can an omnipotent God contradict the law of identity (A = A)?