Funnily, that is exactly what I was arguing with my wife this morning. But I can't really discuss these things with her in a rational manner because she gets frustrated with me. I would never belittle her profession, but as is the case in most relationships, people tend to takes things more personal the closer they are to said person, and so she things I am just stirring the pot (so to speak).
In theory there is a perfect circle, but in reality we will never know. It appears to me that mathematics is very much reliant on being able to be measured: we can only prove the ratio of Pi if we can accurately measure the circumference and diameter; we can only prove the lengths and angles of each side of a triangle if we can measure them; etc.
We can't prove any of these things in reality because we can't measure down far enough – infinity inverted.
Of course, we can try to prove things on paper, and these proofs are good enough to get us to the edge of the solar system and beyond, but they are really only "good enough". We always have to draw the line at some point because otherwise we would spend infinity time measuring something to infinity to find its true value.
Speaking of truth, the truth of the matter is I can't argue mathematics because I'm not a mathematician – not even close. But I can at least argue semantics because I am a wordsmith (at least by trade). That a lot of maths – to me, at least – relies on semantics is proof that it is not actually real.
Maths needs rules – without rules, there is no maths – and so rules are limitations.
Infinity is not limited. So perhaps it doesn't even belong in maths. I suspect it doesn't. That at least gives me grounds to argue its definition.