Translate into predicate calculus notation:
That, that that is, is not that, that that is not.
Is my translation to mathematical logic correct? Thank you for your help!
My explanation: one example would be using the same structure
Love, which love is, is not love, which love is not.
Converting it to logic,
(x) [(Lx is equivalent to Lx) is equivalent to (not Lx is equivalent to not Lx)]
Coming back from love to that, my answer is:
(x) [(Tx is equivalent to Tx) is equivalent to (not Tx is equivalent to not Tx)]
I believe your punctuation is correct, but I would symbolize it quite differently:
$\forall x \forall y (x=y \rightarrow \neg x \not = y)$
In short, whatever something is, is not what it is not.