There's only one rule...

Seems relevant.

"Hello, babies. Welcome to Earth. It's hot in the summer and cold in the winter. It's round and wet and crowded. At the outside, babies, you've got about a hundred years here. There's only one rule that I know of, babies—God damn it, you've got to be kind." God Bless You, Mr. Rosewater

"Love may fail, but courtesy will prevail."
Jailbird, prologue 

“We Humanists behave as well as we can, without any expectation of rewards or punishments in an Afterlife. We serve as best we can the only abstraction with which we have any real familiarity, which is our community.” KV's last speech, April '07

How To Have Productive Philosophical Conversations

When discussing complex topics such as philosophy, skillful conversation becomes even more important. If conversationalists fail to use good technique, then they will not communicate with each other effectively, and the conversation will become unproductive. Let me suggest some ways to make and keep a conversation productive when discussing philosophy.

Listen - Most importantly, you need to listen as well as you can to the other people in the discussion. Many people talk too much and listen too little. Ironically, if you talk too much, you will have a lot of trouble expressing yourself. If you listen well, you can express yourself better because you can tailor your response to what the person has already said. Additionally, if you listen to others intently, they will likely return the favor. If you do not listen to them and just try to talk over them, then they will likely do the same to you.

Ask Questions - Plato's dialogues show how Socrates used questions to have productive philosophical conversations with others. The Socratic Method can come in great use in discussions of philosophy. Asking questions will help you better understand the other speakers, and it will cause them to express their contentions more clearly to you. That will greatly reduce misunderstandings. Additionally, asking questions makes you seem genuinely interested in the other person's ideas. Making disagreeing statements, instead of asking questions, may make the other person feel attacked and may make you seem preachy, both of which will make the discussion less productive.

Speak Clearly - This may seem obvious, but many people instead try to show off or make their ideas seem stronger by using more complex language. However, you will have most productive conversation by having the least misunderstandings, which you can do by expressing yourself as clearly as possible. Using concise, simple, and specific phrasing will usually help you express yourself clearly. Rambling, over-elaboration and the unnecessary use of "big words" will make you less clear. Additionally, you can express yourself most clearly when you match the formality of your speech or writing to the formality of the situation. In other words, use formal phrasing in a formal situation and more informal phrasing in a more informal setting.

Speak Nicely and Politely - If the conversation turns into a contest, or if any of the speakers feel angry or offended, it will greatly reduce the philosophical productivity of the discussion. A discussion about philosophy can quickly degenerate into a name-calling, insult-throwing fight. The other person will listen to you more if they feel more comfortable and respected. Do not just speak as nicely as you must in order to keep the conversation philosophical; instead, speak as nicely, respectfully, and politely as you can. Avoid insults, name-calling, or offensiveness as much as possible. Also, especially if you disagree, try thanking the other person for discussing the topic with you.

If you genuinely try to have a productive conversation, you almost always will. Most people do philosophy for fun out of interest, so why not try to have a productive conversation when discussing philosophy?

Whatever you do, good luck and have fun! 

Scott Hughes

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In A Very Short Intro to Happiness, Daniel Haybron has thoughts on the prudence of imposing reasonable limits on our self-avowed right to express strong opinions aggressively... And Dan Aykroyd, in this old SNL clip, shows us the conversation-stopping and misanthropic/misogynistic force of the word "ignorant"... (Thanks, Anonymous Classmate)
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Avoid ad hominem forms of discourse. It's gratuitous, demeaning, and potentially destructive of free and spontaneous classroom conversation.

Ad hominem is a logical fallacy that involves a personal attack: an argument based on the perceived failings of an adversary rather than on the merits of the case. In short, it's when your rebuttal to an opponent's position is an irrelevant attack on the opponent personally rather than the subject at hand, to discredit the position by discrediting its supporter. It translates as "against the man."

But... let's not get carried away.