22 That this most desirable agreement of wills should be maintained, it is essential that all refrain from giving any cause of dissension which hurt and divide minds. Hence, in newspapers and in speeches to the people, let them avoid subtle and practically useless questions which are neither easy to solve nor easy to understand except by minds of unusual ability and after the most serious study. It is quite natural for people to hesitate on doubtful subjects, and that different men should hold different opinions, but those who sincerely seek after truth will preserve equanimity, modesty, and courtesy in matters of dispute. They will not let differences of opinion deteriorate into conflicts of wills. Besides, to whatever opinion a man's judgment may incline, if the matter is yet open to discussion, let him keep it, provided he be always disposed to listen with religious obedience to what the Holy See may decide on the question.
Source: Graves de Communi Re (Vatican.va)