I read a lot of discussion of "what is science fiction?" on usenet. [1] There were two results for me: a theory that people base their prototypes on strong emotional experiences, but don't recognize that it's their internal process, so they think their idea of "real science fiction" is an objective fact. They get very upset when someone else makes a strong claim that real science fiction is something else.

Actually, I do the same thing. I know someone who believes that science fiction is optimistic. How can he say that Kornbluth and Dick weren't writing science fiction?

The other thing I learned from those discussions on usenet was that I want to avoid discussions of "who's a Jew?". I have successfully avoided them.

Oddly enough, there was one successful definitional discussion-- it was settled that milsf is science fiction about people in a chain of command. This explains why I don't like milsf generally, but do like Bujold's Miles stories.

[1] Is Pern science fiction? It has dragons! On another planet! The dragons are telepathic and can teleport, but (perhaps as a mercy) people tended not to get into the question of whether psi should count as fantasy.

On meta level:

As it happens, no human being employs a language that has been completely purified of all interests, all values, all pragmatic considerations, of everything but the Truth.

Fallacy of gray. Just because we are not perfect, does not mean that some ways are not better than other ways. Humans are not perfectly unbiased, but we could still avoid the most obviously biased arguments.

Liking or disliking a group is not a problem per se. The problem for a rationalist would be if your liking or disliking motivated you to change your own perception of reality (for example by intentionally using non-natural categories) in a way that would make you more likely to believe false statements.

For example, if X% of MRAs believe that women should be chained in kitchens, we should want to believe that the number of them who believe so is X. Not X+1. Not X-1. This is unrelated to whether you consider women chained in kitchens to be the most horrible idea ever, a neutral culture-specific choice, or the best idea ever. One way to change the value of X is to include or exclude the people from the original set, so that the ratio within the new set becomes smaller or greater than X.

Usually, when people do this, they only report the number, and not the difference between the original set and the new set. For example one could say: "I have statistically proved that 100% of MRAs want women to be chained in kitchens (and here are the raw data)" and omit the part "...because I used a definition that only those who want to chain women in kitchens are the true MRAs." There could be other numbers for other definitions, for example "people who self-identify as MRAs", or "people recognized as MRAs by other people who self-identify as MRAs" or "people who agree with MRA ideas, regardless of the fact how they self-identify" (and then we also have to include our definition of "MRA ideas"). And for even greater justice one should also include a number of non-MRAs who want to have women chained in kitchens (instead of silently assuming that it must be zero).

On object level:

'MRA' is a specifically anti-feminist movement

Feminism is not clearly defined, so neither is anti-feminism. Does anti-feminism mean "opposing the voting rights for women" or "opposing job quotas for women" or "opposing how the divorce is typically handled by the courts" or "opposing the idea that all men are rapists and should be castrated"? Any of this? All of this?

'MRA' is already being used as a term of abuse

By some people, yes. By other people, no. Should we also use the word "feminist" to mean "a woman who refuses to shave her legs, and talks about it all the time" just because some people use it this way?

Or does the majority decide? Then most likely for any new movement, the outside definition is "those crazy people".

Generally, opponents of X will typically use X as a term of abuse, and readily provide strawman definitions of X.

EDIT:

I already allowed P5* into the Big Feminist Tent alongside P1-4. I can't allow anti-feminism into the feminism tent, on pain of logical contradiction.

Perhaps the ability or inability to be included in the Big Feminist Tent is not the essence of MRA. We should look at the essence independently.

Imagine that you already have a category called Apples. Now someone proposes a category of Green Things. It would be strange to say: "Let's define Green Things as those things which are green and are not apples... because the green apples are already included in the category Apples."

Some green things are apples. Some green things are not apples. Even if there is a correlation between green things and apples, it is still better to define Green Things as being green, instead of being green non-Apples. (That is not the same as asking someone to include also the green non-Apples into Apples, which would be a logical contradiction.) The definition of Green Things is unrelated to the definition of Apples.