We all share basic ideas about right and wrong. These basic ideas don't contradict each other. Who among us doesn't think that good things are helpful and worth choosing? Who doesn't think we should always follow and pursue what's good? Who doesn't think justice is noble and proper? So when do disagreements start? They start when we try to apply these basic ideas to specific situations. One person says, "He did the right thing. He's brave." Another says, "No, he acted like a fool." That's when people start arguing. This is what Jews, Syrians, Egyptians, and Romans argue about. They don't disagree that holiness matters most and should always be pursued. They disagree about whether eating pork is holy or unholy.
ON PRÆCOGNITIONS.—Præcognitions are common to all men, and præcognition is not contradictory to præcognition. For who of us does not assume that Good is useful and eligible, and in all circumstances that we ought to follow and pursue it? And who of us does not assume that Justice is beautiful and becoming? When then does the contradiction arise? It arises in the adaptation of the præcognitions to the particular cases. When one man says, "He has done well; he is a brave man," and another says, "Not so; but he has acted foolishly," then the disputes arise among men. This is the dispute among the Jews and the Syrians and the Egyptians and the Romans; not whether holiness should be preferred to all things and in all cases should be pursued, but whether it is holy to eat pig's flesh or not holy.