For example, what are your feelings about tomatoes? You either like them or you don’t. But do you know why? Nope.
So is anything not like that?
Everything we do is governed by two primal instincts: to seek pleasure and to avoid pain. Of course what we consider “pleasure” and “pain” varies widely—but the principle holds.
Are you religious or not? Either way, you can probably cite a bunch of intellectual reasons, but it’s an emotion-driven choice. That’s why people can argue religion till they’re blue in the face and not budge an inch.
People even kill each other over religion. Lots of them—even here in the 21st century. Yet those same people would consider it a silly waste of time to try to convince each other they should like or dislike tomatoes.