User blog comment:VoidSansXD/Ordinal notation./@comment-35470197-20190228024246/@comment-35470197-20190228034517

Thank you. Yeah, actually I know it. However, I guess that the OP does not. It is not good for us to rob the OP of the opportunity to learn what the OP is actually writing and how to write a definition.

It does not matter if the OP only creates eventually well-defined stuffs, but the OP will someday create completely ill-defined stuffs by extending other own stuffs without understanding them. Then even if we point out the problems, the OP would not understand the problems at all by thinking "But similar constructions were always accepted. What is wrong now?" In that case, we have no way to help the OP. That is why I think that we need to have the OP understand the problems before stepping in complicated mathematical stuffs. I am sorry if you think that I am incorrect.