And the way we feel towards others is an important part of it, even more than what we think of their viewpoints, maybe. In other words, if I can feel empathy and love towards someone I think has weird ideas ("What she's saying/doing doesn't seem right to me---but then again, think how many times I've been wrong about something I was sure of, and also how many times I've done the wrong thing even when I knew what the right thing was---so she is probably just trying to make sense of things just like I am. I know how that feels.") then I am less likely to set myself apart as "better" than others. I think one of the most harmful attitudes to have is this one (which I find myself falling into all the time): "Sure, I'm not perfect, and I have my problems, but at least I don't do _____!" (Or, "at least I'm not as bad as _____ is!") I think the whole point of all the scriptures on charity and love for your fellow-men, is to emphasize that we all are in exactly the same boat: no matter HOW good we are, NOBODY is "good enough" without Christ, and we all need His atonement equally. I think I used to have the idea that we all needed the atonement, but some people sort of needed it less than others. Now I think that's wrong. I think we're all (really, all, even people like Joseph Smith or President Monson) equally lost without the mercy of God.
So, back to unity, I'm starting to think that simply being able to say to several different viewpoints: "Yes, thats a good point; that's a good point too; yes, I can see your point too" is not really enough to strive for. I mean, that's fine, and it might help you get in fewer arguments, but maybe the main thing is to find love or understanding or sympathy towards the person themself. And worry less about if you disagree with their politics or their views on polygamy or whatever. (And so does that mean that you just avoid any touchy subject? Only talk about things you DO agree on? Maybe so, at least sometimes. I was thinking maybe that wasn't truly being "of one heart and one mind," but maybe if it makes you feel more charitable, it's a good start.)
The other thing I think is involved is that just like in a marriage, how both partners have to give 100% for it to work---for true unity, probably everyone has to be making the effort, and if everyone isn't, it may not work quite as perfectly. But I assume that if even half of the people, or 20% of the people, in the church tried harder, things would be noticeably better. [And I think I am talking mostly about unity in the church, here. I'm taking for granted that we need to be able to get along with other faiths and people who don't believe in God, and we need to make our voices heard on public policy so we don't support things we think are morally wrong, etc etc etc.---but what got me started on this whole thing was just thinking that even within our own church, it seems impossible to achieve unity. But it must be possible, because we're supposed to try for it. Right?]
I've been trying to think of people I know who seem to have this kind of benevolent attitude towards other people with different views (my teacher Leslie Norris comes to mind, as does President Hinckley, and some people in the ward I grew up in) and many of them were older when I knew them, and maybe they had just had more life experiences that taught them this very thing: that everyone has their struggles, and you can't really feel superior to anyone because you are just as foolish and vulnerable and dependent on God as the next guy. I feel like maybe when I have fewer of my own insecurities (or have learned to deal with them better), I won't feel so defensive and so anxious for other people to agree with me. (Because a lot of times we say we just want other people to "respect our views," but I think often, we really want them to do more than that---we want them to actually agree; to think we are right.) And maybe as we get older and wiser and see more of life, we will be content to look at other people, and even if we don't feel totally in unity with what they think or what they do, we will feel unified in that we are all flawed and human and we all need love and we all need God.
Can we do anything to hasten ourselves towards that attitude, I wonder? I think I'm closer to it than I was ten years ago, but I still wish I was much better. I guess we can just work on getting into those thought patterns, of generosity towards others---giving them the benefit of the doubt---remembering your own mistakes and flaws---etc.