Almost all fights/arguments come out of misunderstandment. It's not always misunderstanding the situation itself but what led the other person to this situation. Why is he/she saying this? It's hard enough to also understand what a person is saying. But once you understand both, it's hard to be upset.

My other most important value; let others be others. You and everyone can do as you like as long as no one is forced into it as well. Example: someone going through abortion with a fetus not capable of feeling does not affect anyone since it's unknowing and the abortion itself doesn't force others into a debate or partaking. However, denying the possibility of abortion will limit the person wanting abortion.

Edit: what brought me to this was just pure experience and socialization. My second girlfriend helped me get to the first point. The other one I guess my parents instilled.