I don't think your friend's point of view is impossible to argue against (as I mentioned in my other comment you can argue based on results)
I'm talking hypothetically. I did allow myself to consider the possibility that the idea was not perfect. Actually, I assumed that until I could prove otherwise. It just seemed pretty hopeless, so I'm considering the extreme.
it's not obvious to me that you've correctly understood your friend's point of view
Maybe not. I'm not angry at my friend at all, nor was I before. I felt sort of betrayed, but my friend had reasons for thinking things. If (I think) the things or reasons are wrong, I can tell my friend, and then they'll maybe respond, and if they don't, then it's good enough for me that I have a reasonable interpretation of their argument, unless it is going to hurt them that they hold what I believe to be a wrong belief. Then there's a problem. But I haven't encountered that yet. But the point is that it, to me, is much more interesting/useful/not tedious to consider this idea that challenges rationality very fundamentally, than to try and argue against the idea that everybody who had tried to apply rationality to society had it wrong, which is a very long battle that needs to be fought using history books and citations.
I still think you are focusing too much on the semantic content of the conversation.
Then what else should I focus on?
You are a human, and humans get angry for a lot of reasons, e.g. when other humans challenge their core beliefs.
I like having my beliefs challenged, though. That's what makes me a rationalist in the first place.
Though, I have thought of an alternate hypothesis for why I was offended. My friend compared me to white supremacist philosophes from the early days of the Enlightenment. And when I said that I did not share their ideas, my friend said that it was not because of my ideas, but because I was trying to apply rationality to society. And maybe that offended me. Just because I was like them in that I was trying to apply rationality to society (which I had rational reasons for doing), I was as bad as a white supremacist. Again, I can't be mad at my friend, since that's just a belief they hold, and beliefs can change, or be justified. My friend had reasons for holding that belief, and it hadn't caused any harm to anybody. But maybe that was what was so offensive? That sounds at least equally likely.
But the point is that it, to me, is much more interesting/useful/not tedious to consider this idea that challenges rationality very fundamentally
This is what I mean when I say I don't think you've correctly understood your friend's point of view. Here is a steelmanning of what I imagine your friend's point of view to be that has nothing to do with challenging rationality:
"Different domain experts use different kinds of frameworks for understanding their domains. Taking the outside view, someone who claims that a framework used in domain X is more a...
Usually, I don't get offended at things that people say to me, because I can see at what points in their argument we differ, and what sort of counterargument I could make to that. I can't get mad at people for having beliefs I think are wrong, since I myself regularly have beliefs that I later realize were wrong. I can't get mad at the idea, either, since either it's a thing that's right, or wrong, and if it's wrong, I have the power to say why. And if it turns out I'm wrong, so be it, I'll adopt new, right beliefs. And so I never got offended about anything.
Until one day.
One day, I encountered a belief that should have been easy to refute. Or, rather, easy to dissect, and see whether there was anything wrong with it, and if there was, formulate a counterargument. But for seemingly no reason at all, it frustrated me to great, great, lengths. My experience was as follows:
I was asking the opinion of a socially progressive friend on what they feel are the founding axioms of social justice, because I was having trouble thinking of them on my own. (They can be derived from any set of fundamental axioms that govern morality, but I wanted something that you could specifically use to describe who is being oppressed, and why.) They seemed to be having trouble understanding what I was saying, and it was hard to get an opinion out of them. They also got angry at me for dismissing Tumblr as a legitmate source of social justice. But eventually we got to the heart of the matter, and I discovered a basic disconnecf between us: they asked, "Wait, you're seriously applying a math thing to social justice?" And I pondered that for a moment and explained that it isn't restricted to math at all, and an axiom in this context can be any belief that you use to base your beliefs on. However, then the true problem came to light (after a comparison of me to misguided 18th-century philosophes): "Sorry if it offends you, I just don't think in general that you should apply this stuff to society. Like... no."
And that did it. For the rest of the day, I wreaked physical havoc, and emotionally alienated everyone I interacted with. I even seriously contemplated suicide. I wasn't angry at my friend in particular for having said that. For the first time, I was angry at an idea: that belief systems about certain things should not be internally consistent, should not follow logical rules. It was extremely difficult to construct an argument against, because all of my arguments had logically consistent bases, and were thus invalid in its face.
I'm glad that I encountered that belief, though, like all beliefs, since I was able to solve it in the end, and make peace with it. I came to the following conclusions: