He who knows only his own side of the case knows little of that. His reasons may be good, and no one may have been able to refute them. But if he is equally unable to refute the reasons on the opposite side, if he does not so much as know what they are, he has no ground for preferring either opinion… Nor is it enough that he should hear the opinions of adversaries from his own teachers, presented as they state them, and accompanied by what they offer as refutations. He must be able to hear them from persons who actually believe them…he must know them in their most plausible and persuasive form.
- John Stuart Mill
I appreciate this level of introspection. I think you’re right to keep an open mind and to seek a broader view of the issues, but don’t be afraid for the conclusion you draw to be that someone or some opinion is ignorant, bigoted, or hateful. You should be open to any possibility… but as anticlimactic as it is, sometimes something really is black or white; that’s a possibility just like any other. Understanding why someone hateful thinks the way they do is useful, but it doesn’t change the fact that they are.
TL;DR: If you never consider other viewpoints, you’ll never find the right one, but if you never stop considering them, you’ll never find the right one either. I wish you luck in your pursuit of knowledge.