User blog comment:P進大好きbot/Whether Rayo's number is well-defined or not/@comment-25601061-20180606221005/@comment-35470197-20181027130059

When I read back my blog post, I found that my statement was ambiguous, because "even if one adds mathematically precise descriptions to the original definition" can be read as "even if one adds an arbitrary strong axiom". (I would not like to state such a non-sense one, because you can add the strongest axiom \(0 = 1\). Then everything is well-defined, because the formal system derives contradiction.) I am sorry for the ambiguity. I was just thinking about possible formulation under \(\textrm{ZFC}\) set theory.