> How do we know that other H sapiens have the same kind of experiences of existing as you have? Best I can do is that "I know, right?" is a fairly universal reaction, so we know that even if others' qualia are not identical to ours, they are at least isomorphic.

Seeing my own phrasing echoed back, I notice an ambiguity: "the same kind" can be either "all the same things" or "it is kinda close".

The former is provably different between humans: aphantasia, gender dysphoria, sexuality (including the absence), ASD, the conservative/liberal divide, that some people describe having religious experiences and others don't, amusia, … there's so many ways to be different, I'd be surprised if any of us is entirely "normal".

I meant the latter. And the only positive evidence I have for that, is that other people were writing about it before I was born… which doesn't actually tell you that I have it, as for all you know I might be a P-zombie that's just parroting phrases it once read, I'm the only one who can be sure that there's an "I" in this body of mine.