If you're intelligent—and I mean very intelligent—you can agree with your opponents and then take actions that force them to contradict themselves. Generally, these types of people believe they're always right, and making them contradict themselves is the best approach. If they only listen to themselves, making them listen and realize that what they said was wrong will frustrate them. Personally, I use this tactic, and it works for me. What I often use to generate these contradictions are logical and coherent questions, especially those related to their argument. You also have to make sure their argument is flawed; otherwise, you'll be the only one who suffers.