Whether it is lawful to have various contrary opinions of notions?

❌ Objection 1 : It would seem that it is not lawful to have various contrary opinions of the notions. For Augustine says (De Trin. i, 3): "No error is more dangerous than any as regards the Trinity": to which mystery the notions assuredly belong. But contrary opinions must be in some way erroneous. Therefore it is not right to have contrary opinions of the notions.

❌ Objection 2 : Further, the persons are known by the notions. But no contrary opinion concerning the persons is to be tolerated. Therefore neither can there be about the notions.