User blog comment:Emlightened/Little Bigeddon/@comment-1605058-20170106113726

Few minor comments: first, in the \(T\) axiom in the second line, you needn't state that \(e\) exists uniquely - if \(d\) is an ordered pair, then it is so in a unique way. However, you might want to require that for each \(e\) at most one pair \(\langle e,f\rangle\) appears (maybe this is what you meant?).

I think this is a typo, but I might be missing something: when defining \(\texttt{rk}\), in the last line one \(\texttt{fr}\) appears.

In the definition of \(form_0\), you write e.g. \(\land i,j<\omega\), does this mean the same thing as \(i,j<\omega\)/\(i<\omega\land j<\omega\)? I have never met such a notation.

Apart from that, I'm quite impressed by how precise you were with defining this language. I'd say this is a large number worth losing to :)