One way is to ask questions. The first way that most of us think to confront someone is to make statements: "You're wrong." Even impersonal facts, like "Solar

One way is to ask questions. The first way that most of us think to confront someone is to make statements: "You're wrong." Even impersonal facts, like "Solar is now cheaper per watt than coal" is unlikely to persuade your opponent, partially because they can tune you out as you ramble on. But if you ask a question, they have to listen closely, to avoid looking foolish when it's their turn to talk. A direct question is also more likely to lead them to think. Furthermore, a question is more polite. A question can still be devastating, "If you think x is better than y, then how do you account for (insert hard fact here)."