These apply to 1:1 discussions and not if you have an audience. If you have an audience, these rules can more or less reverse (depending on the audience). This list isn’t exhaustive.

1. Confidence by itself generally loses out over evidence when all participants are equally reasonable.
2. Not all people that seek out debate in casual conversation are equally reasonable.
3. Don’t confuse prejudice with argument, and never make a personal comment part of your debate – you cede all authority.
4. If you can’t resolve the debate in the cold light of sobriety it won’t suddenly make sense intoxicated.
5. “Let’s agree to disagree” is a polite way of saying “I have no desire to pursue this conversation” and gives any participant in an argument the option to gracefully exit without giving up their perspective.

I’ve found myself in the position of defending people, products and positions I’m not particularly a fan of recently because people violate these rules in conversations with me. I’m not one to generally take a stand on random principles these days, but do find it hard to let totally unreasonable, unfair statements about anything stand. One of life’s little ironies.