We show that an essential assumption in the Vafa-Witten theorem on P and CT
realization in vectorlike theories, the existence of a free energy density
in Euclidean space in the presence of any external Hermitian symmetry brea
king source, does not apply if the symmetry is spontaneously broken. The as
sumption that the free energy density is well defined requires the previous
assumption that the symmetry is realized in the vacuum. Even if Vafa and W
itten's conjecture is plausible, actually a theorem is still lacking.