The word "ex postulated" refers to something that has been assumed or inferred after the fact. Its antonyms include "proven," "demonstrated," "established," "confirmed," and "verified." These words all imply that something has been backed up by evidence or facts, rather than just an assumption. Other antonyms for "ex postulated" might include "refuted," "disproved," "discredited," "invalidated," or "debunked," which suggest that an original assumption or hypothesis has been proven false. Overall, the antonyms for "ex postulated" emphasize the importance of supporting claims with evidence and the need for critical thinking and careful analysis.