To add, personal experience can be useful, but is not the end-all in decision making. It's useful in the ways anecdotes are useful, that is to say, good as an illustrative example but may not be statistically representative.

In general, you do not need to have personally experienced X to have a useful or "valid" opinion on X. As a reductio ad absurdum, nobody would be allowed to have an valid opinion on murder.

No one advocates that you should only speak if you lived it, we say that those who lived it must have a say if that is in any way possible.

The original question was

> how much of this nuance is achieved by having discussions about issues which have real life-or-death impacts on people but without having any of those people inconveniently present?

Followed by an assertion that

> A group of X people is [not] capable of of empathising with, understanding and having a nuanced opinion of the concerns of !X people

So I think there are people advocating that you should be speaking only if you lived it.

Of course, anecdotes and personal experiences are valuable and including people with personal experience is helpful, but the central claim here is that you can have productive discussions about X without anyone with personal experience with X.

I reject that discussion will be inherently flawed without representation. I further submit that representation can cause flaws in discussion.

To use your thought experiment as an example, say if we are critically examining Sumerian religion and their creation myths, we may not want the Sumerians in the room even if they were readily available, since they may well take offense at us disrespecting and dissecting their beliefs. If we are discussing Sumerian religion with Sumerians and we don't want to cause them offense, we would have to tiptoe around the fact their gods well, aren't real, and subjects like "what might have inspired the Sumerians to ascribe this trait to that god" can't be discussed at all.

And to use a example more grounded in reality, a group of men can't have properly conduct a discussion on how to attract women with women in the discussion. I am well aware that this sort of discussion has pejorative connotations with how infamous the PUA community has become, but the fact is that young men do need to social spaces and groups where they can learn this, since it is skill that needs to be learned and practiced.

Or to use an even more absurd example, a group of rape victims can't have a discussion with a rapist, even though the rapist would be able to add their side of the story to the discussion.

    if we are critically examining Sumerian religion 
    and their creation myths, we may not want the Sumerians 
    in the room even if they were readily available, since 
    they may well take offense at us disrespecting and 
    dissecting their beliefs.

I would agree with this specific example.

Religion is a special case when it comes to rational discussion. It is explicitly a belief in the irrational, and is not compatible with rational thought.

When the "out group" decides to exclude the "in group" from a discussion, we should be very very sure that there's some highly specific reason why the "in group" is simply incapable of rational discussion.

For example, we exclude my car from discussions about his medical care because he is a cat and he can't speak or understand medicine. If we do that with people, we need to be very careful.

    And to use a example more grounded in reality, 
    a group of men can't have properly conduct a 
    discussion on how to attract women with women 
    in the discussion. 

This is completely opposite to my experiences.

I certainly think it's healthy and good for men to discuss sex, attraction, etc, without women as well. Heterosexual men are a part of the group that experiences dating and sex with women. (I wonder how many hours of my life I've spent on this? Thousands? Tens of thousands?)

This is markedly different than, say, a panel of men discussing/deciding things for women, i.e. a panel full of men deciding what women can and cannot do with their bodies.

    a group of rape victims can't have a discussion 
    with a rapist, even though the rapist would be 
    able to add their side of the story to the discussion. 

I agree with caveats. (Some victims find power and closure by confronting their rapists, etc.)

To generalize this specific example into something broadly applicable, the reason why this example works is because in this case the rapist has done something highly transgressive - essentially, they have broken anything that might reasonably be considered a social contract - and it would certainly be reasonable for a rape victim to find it highly upsetting to see their rapist, much less listen to them.

So again, I would say the validity of excluding a person from a discussion relevant to them would highly depend upon some explicit evidence or reasoning that productive discussion simply cannot occur if they are a part of it.

This would not apply to, say, a room full of white people deciding things about the Black experience.

I think given the context of this thread, it’s fair to mention that there are plenty on the internet who use that kind of rhetoric to invalidate any out-group opinions they don’t like. Not everyone of course, but it happens. These are some of the conversations that are lacking nuance. Sometimes the out-group has something to offer. Sometimes you just need to make them feel heard before you explain to them what they’re not getting. It’s about having the conversation. Why should anyone listen to someone if they don’t get the same respect back?

    Sometimes you just need to make [the out group] feel 
    heard before you explain to them what they’re not getting. 

When you listen to groups of affected issues, what you often hear is that they have been explaining forever, it hasn't worked, and frankly they're exhausted.

Often, the folks who ask them for "explanations" are doing so in bad faith. Perhaps you're doing so in good faith, but they have a right to be wary and/or weary.

Understand that a group being oppressed or affected by some injustice is already bearing an undue burden.

    Why should anyone listen to someone if they don’t get the 
    same respect back?

In some cases, you may be the one being incredibly disrespectful by expecting some sort of explanation, because tons of explaining has already been done.

To name one example, there is an incredibly rich history of African-American writing, art, and other forms of expression regarding the African-American experience. To use the mildest possible word I can bring myself to type, it would be rude to expect any individual to owe me some sort of explanation. Why should they do the work of explaining (yet again, most likely) when I haven't?

Look, I get where you're coming from, but this post was specifically about places to find nuanced discussion on the internet, and in the context of that, responding to

> No one advocates that you should only speak if you lived it, we say that those who lived it must have a say if that is in any way possible.

I stand by what I said. If you're coming to the table for nuanced discussion, I don't think it makes much sense to shout down your opponent with ad hominems simply because others have argued against you in bad faith before. If you're weary of explaining something, I get that, but I don't think coming to a place full of people looking for a nuanced discussion and calling them names when they may basically be on your side already does your cause any good. I understand it, and it's a completely human reaction, but it's alienating.

Oh, "they" don't advocate. "They" are very careful not to advocate. But ask questions? Suggest? Leave historical links to wikipedia? God, I'm starting to hate this whole thing with a burning passion.

Not the poster, mind you - clicked through its history and he's a decent fellow. Or fellowette. Rather like him, actually.

But the whole memeplex that seems to grow and grow to the point it actually has rules on how to breach topics on public forums... that I do begin to really hate.