Based on several recent conversations with friends:

Rule 1:  Don't assume you know the background of the person you're talking to.  Judging someone by their appearance isn't fair, nor liberal.  Disabilities don't always show.  Culture, religion, background rarely show, nor does gender orientation. Pigeonholing people is not very tolerant, nor liberal.

Rule 2:  Anyone can discuss an issue.  They may not be correct, or they may not agree with you, or some of each or both.  Telling people they don't get to discuss an issue is not going to convince them you're right.  It's only going to convince them you're conceited.

Rule 3:  If it's a technical subject, such as firearms, reproductive biology or even a religious faith, the technical knowledge is a necessary part of the debate.  Don't claim to be "informed" if you can't answer basic technical questions on the subject.  In such cases, it would behoove you to acquire some technical knowledge, or to consult with someone who does.  Here's the tough part: You have to assume they know what they're talking about, and believe their statements, much as you would a professional in any field.  If the facts make your position uncomfortable, then perhaps your position needs to change.  You are entitled to your own informed opinion.  You are not entitled to your own facts.  And if your opinion is not informed, you're still entitled to it, but no one is obligated to take you seriously.  

3A: If you don't trust a person's technical opinion, why did you ask for it?  Getting a second opinion is fine. Asking other people who are ignorant of a subject to fact check the expert is not only insulting, it indicates you need to re-read this rule.  If most of the subject matter experts tell you you're wrong, maybe you are. This doesn't mean you have to like the conclusion. You only have to accept it.

Rule 4:  Once you've demonstrated bias through ignorance, your credibility on any other matter drops fast.  See Rules 1 and 3.

Rule 5:  It's entirely possible for someone to have the same or different sources, be informed, and come to a different conclusion.  This does not mean either you or they are wrong.  Few issues are binary in nature.  This offers an opportunity to debate, share information, and improve your position, even if you never fully agree with the other party.  And that's okay, because liberals are tolerant of dissent.

5A:  Don't assume that someone disagreeing with you must be ignorant of the subject.  Ask questions.  Learn why they have their position.

Rule 6:  If you are absolutely sure the other party is wrong by your interpretation, remember that you also don't know everything, and even matters of common knowledge change with time. This person may be comfortable in a previous or foreign culture, or they may be ahead of the curve and ready for a future society.  More likely, the answer lies somewhere between.   

Rule 7: Activists don't have to compromise.  They're expected to be extreme.  If this applies to you, remember it also applies to others.  They're entitled to the same focus and drive you are.

Rule 8:  Skin color only matters to people who care about skin color.  A person with dark skin may be from somewhere Africa, the Caribbean, or the US or anywhere else.  Each of these people will have a different background. Their skin color only affects how you treat them, and how you treat them affects how they respond as a person.  If you make assumptions about them based on their skin color, you're being presumptuous.  Likewise, a white skinned person may be from the US, from Europe, from Australia.  They're not going to all be the same, either.  In fact, even American geography matters.  However, it's likely that two Americans (or Canadians, Aussies, Greeks, Chinese), even of differing appearance, will have more in common with each other than with two people who look the same from different nations.  If this is a revelation to you, you may not be as unbiased as you like to think you are.

8A: If you're a middle class white American, lecturing people on how middle class white Americans shouldn't lecture people on race/color/culture, you may have run into a recursive logic failure.  Also, if you're assuming from visual cues that the person you're debating with is a middle class white American just like you...see Rule 1.

Rule 9:  Telling someone else how they think or feel is conceited, derogatory, and wrong.  Please don't do it.

Rule 10:  You know how the popular press always gets your subject wrong when they discuss it?  You know how the opposing press leaves out key facts through error or deceit and presents you in a bad light?  It's a good idea to assume the same thing happens with other subjects and to other groups.  See Rule 3.

Rule 11:  Epithets like "right winger" and "wingnut" and even "troll" don't encourage the other parties to continue discussion.  They're also neither liberal nor tolerant.  Unless you plan on exterminating or outbreeding the dissenters, you need to patiently try to persuade them.  Some won't be persuaded.  This is not your fault.  It may not be their fault, either.  All you can do is try.

Rule 12:  Selection bias doesn't help.  Seek out opposing viewpoints.  You may change your own.  You may strengthen yours.  You may change or strengthen theirs.  Worst case, you'll know how the opposition thinks and feels, and so will your allies.  Holding carefully monitored discussions with your friends isn't a bad thing and has its place.  But it's not an open discussion.  Keep private matters private, and allow public discourse to be open. And echo chamber is not very useful.

Rule 13:  If you're thinking of deleting, blocking, shutting down a dissenter or a thread because you don't like how the discussion is turning, you may not be as tolerant as you like to think you are.  Certainly there are absolute trolls who contribute nothing.  But a dissenter is useful under Rule 12.

Rule 14:  Shocking fact:  These same rules apply to conservatives.  You may in fact find fora where you're tolerated and treated with respect.  You also may find some where you're insulted and called a troll. You can complain about this...if you haven't committed the same act yourself.

Rule 15:  Nothing is binary. There are pro-gun gays and feminists.  There are anti-abortion atheists.  There are black racial separatists.  There are pro-gay Muslims and Pentecostal Christians.  There are polyamorous Republicans.  See Rule 1.

Rule 16:  Even among people of the same general background, individuals have different experiences and perspectives.  What's wrong for you may be right for them.  Or it may simply be they're a product of their experiences.

Rule 17:  If everyone agrees with you, you need to widen your circle.  If you're not angry at something at least once a day, you're probably not learning anything.

Rule 18:  Yes, it gets frustrating re-hashing the same material.  If you've adopted the mantle, you have to try to be patient.  Unfortunately, it's the only way.  See Rules 11 and 13.

Rule 19:  Some of your opponents will love you even though you're wrong.  Try to extend them the same courtesy.

Rule 20:  There is nothing morally wrong with apologizing.  If you were perceived as offensive, or lost your temper, or even just misunderstood, apologize and try again.  Often, that will make more progress than any number of graphs and charts.

If you look for racism, you will probably find it.

Let's consider science fiction:

If your black characters act like white characters, they're tokens, and you're a racist.

If your black characters act like black characters, they're stereotypes, and you're a racist.

If your black characters are in the forefront, you don't consider them capable of command, and you're a racist.

If your black characters are in command (Nick Fury, forex), then you don't have them in the forefront, and you're a racist.

If your black characters are good, they're shallow, and you're a racist.

If your black characters are villains, they're caricatures, and you're a racist.

If your black characters sacrifice themselves for the white characters (Phantom Menace, even though they weren't actually black, and Revenge of the Sith), they're throwaways and you're a racist.

If your black characters are saved by white characters, they're incompetent, and you're a racist.

If your black characters are kept safe, we're back to them being tokens, and you're racist.

If you decide not to mention race and let people draw their own conclusions about the characters, you're passive-aggressive on the subject, and a racist.

If you have a future where people have given up racial issues and interbred all genetic lines, then you've destroyed black race and culture, and you're a racist.

If you don't have Africa ascendant at some point in the future, because you believe environmental and political issues won't support that in your given timeframe, you're a racist.

If Africa is ascendant in your work, but contemporary mores would find your culture offensive, you're fabricating false perceptions and you're a racist.

If your future Africans choose a development that makes them too western, you're provincial and a racist.

If your black characters are conservative and successful, they had to sell out to have a place in your universe, and it's a racist culture.  You're also a racist.

If you observe that Americans are predominantly white, the SF readership are predominantly white, and white writers don't get much reader attention from the black community, you're a racist.

If you decide all this is too complicated and don't use any black characters, you're definitely a racist.

The above only applies to a white writer.  A black writer can use their characters any way they wish.  If you complain about them overdeveloping black characters over their white characters, you're a racist.

A non-white, non-black writer writing about black characters gets a partial pass, if the liberal establishment likes their political position.  It's entirely possible for an other minority writer to be racist.

If you try to analyze perceptions in order to make a better presentation of black characters, and discuss those issues online, you're a racist.

Based on research I'm doing for a story.  I have no idea if this ever existed, and I don't think anyone else does.  It works with materials that would have been easily available, however.

This is flexible, so it's easy to do wherever you are.

Slice your chicken into thin strips.  This also works for goat.

Hot pan, hot rock, hot oven stone.

Sprinkle with rock or sea salt.  Add some chopped scallion/wild onion/chive.  Add rosemary or similar evergreen herb.  The greens will likely pop and jump on the hot surface.

Lay the chicken down on the bed of salt and herbs. Once the edges are white, flip over.  Cook until lightly brown.

In a pan, you can also pour in some brine in small drops, to sizzle under the meat.

For cooking on a grill, dredge in the salt mix before laying over the grill.

you can add vegetables if you wish.

My kids insist I cook this regularly.

Observed fact:  Gays were not able to marry in the US for the duration of its existence, nor in the colonies before, until the last decade.  No harm came to the US from this standard (Which was pretty much the world standard).  So, if SCOTUS rules against this issue, the safety and existence of the United States is not in jeopardy.

In the last 15 years or so, several nations and several states have legalized gay unions and marriages.  There are no observable direct or indirect repercussions causing damage to the political existence of these jurisdictions.  So, if SCOTUS rules in favor, the safety and existence of the United States does not appear to be in jeopardy.

Every opposition to the matter I've heard comes down to either "Our religion doesn't like it," or "We've never done it that way."

Setting aside the religious question as not admissible in court, we come down to, "At the time the nation was founded, marriage was between one man and one woman."

And for the last two months, the Left (including a large number of gays) has been bleating that, "At the time the Constitution was written, 'arms' referred to muskets'" as an argument against any firearm designed after the 1870s.

So, logically, there are no arguments for, and the Left's own logic against.

Argument in favor of gay marriage fails for lack of support, and lack of logical consistency.

Unless, of course, the Left would like to compromise and concede that as time progresses, society and technology do, too.  Then, they must apply that argument fairly to groups they don't agree with.