 It is often said that given a property denoted by \(A(x)\), the sentence \(D\) is a self-referential sentence which “says of itself” that it has the property \(A\). Such figures of speech may be heuristically useful, but they are also easily misleading and suggest too much. For example, note that the lemma only provides a (provable) material equivalence between \(D\) and \(A(\ulcorner D\urcorner)\) (which states that both sides must have the same truth-value) and does not claim any sort of sameness of meaning. In particular, \(D\) and \(A(\ulcorner D\urcorner)\) are by no means identical—and neither are \(\ulcorner D\urcorner\) and \(\ulcorner A(\ulcorner D\urcorner)\urcorner\). 