Listen very carefully to others. Maybe you will learn something, maybe they just confirm your initial impression. Often people speak to express their mood, not to convey information. Also, when people talk very passionately about their opinions of other people, they are often speaking indirectly about their feelings towards themselves.
Never interrupt. Never contradict, Never insult. These are low-value tactics in a verbal conflict. By not using them, you make it much harder for other people to use on you. If other people interrupt, contradict, or insult you, ignore it. By 'contradict' I mean don't say 'No, that's wrong...' Just say the correct thing and stop. So if someone says 'wheels are square, everybody knows that,' just say 'wheels are round,' and stop talking.
In general, it's a good idea to say as little as possible until the other person runs out of things to say, especially if they're angry.
Repeat what other people have told you. Ask simple questions, ideally with yes/no or very definite answers. It will be much easier to tell if the other person is lying. Also, ask questions that you already know the answer to, in order to get the other person to follow the direction you want in conversation. this is a technique trial lawyers use a lot.
When you use these techniques in an argument, it's like you step out of the way if someone tries to hit you. The other person swings his fist - you move aside. You can lead the person where you want to go by the way you move. They waste their energy expressing anger or saying foolish things. When you speak, you are very careful to say only things you are sure about.
Avoid trying to jump ahead of the conversation to guess what someone really means or what their secret motivation is or anything like that. Often such guesses are wrong, and in any case it often doesn't matter.
Smart people are never afraid to say 'I don't know' or 'I don't understand, please explain' or 'I'm confused about ______.' If you make a habit to be honest about this instead of pretending to understand something you don't, you'll find it's hard to for other people to lie to you.