User blog comment:DontDrinkH20/H-Boogol-Boogol: Hopefully a very big non-salad number/@comment-35470197-20180819021045/@comment-36540075-20180821050040

AH! Ok, now I see. To answer your first question, a simple modification of ZFC variables with another symbol could be used where \(xAAA\) is the third variable, and \(xAA\) is the second, etc.

To answer your second question, perhaps it is not well-defined in ZFC and requires ZFC + 2nd order specification.

If I made it all definable classes though, would it work with normal specification? Thank you for these very informational comments!