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’d like to think that most people do this, but unfortunately I know better. I would like to say, however, that it’s possible to make your own independent decisions about each issue, have them align with one party more than the other, and then identify with the party that your views align with. As long as your views define your party, rather than your party defining your views, there is nothing wrong with identifying with the party that you’re closest to.