Math Is Hard said:
You might be reading more into this than I intended. I was describing the effects (the particular feeling of disgust) rather than the causal mechanisms (what creates the disgust).
If you can express this opinion without disgust, and without any attraction to your own gender, then on my scale you are about 99.9% heterosexual. This is just my own view of the extremes and in-betweens of the hetero-bi-homo continuum. You are free, of course, to create your own. You and I just probably differ on what those extreme ends of the scale are.
Off on a tangent, I’m interested in understanding this post better (but for the record, to the op, yes).
I think I see you are saying that it is impossible to subjectively evaluate solely objectively. I don’t see where the emotion of disgust comes into it, and causal mechanisms, and am interested in understanding that.
One thought is that it would be evolutionarily advantageous to be able to determine to some extent the competition, thus, beneficial to heterosexuals to determine the sexiness of their competitors-others of the same sex. I don’t know whether this is a counter to the premise that ‘pure’ straights must not be able to see their own sex as sexy and that they can, whether it a counter to ‘pure’ heterosexuality, or whether it is evidenced in the bad summations some people make about what attracts the opposite sex

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Were it to counter the premise, I would add imagination, and that the empiricists especially and Samuel Taylor Coleridge with his ‘consciously paradoxical’ ‘willing suspension of disbelief’ write of how art can stir emotions that have no direct cause. If we can have feelings that aren’t directly provoked and seem not entirely about reality, when, say listening to music or reading a book, does this make it plausible that ‘pure’ straights and can appreciate members of their own sex as sexy without feeling remotely attracted? Whether or not this is an attack on the premise I think involves whether imagining an emotion already felt (sexual attraction) can extend to a different orientation. Also, importantly, it would depend on how real these imagined emotions are. This is all tricky to think about, not being of a ‘pure’ heart (bad pun), but if I believed what I am musing about, then perhaps I should be able to imagine even this.
Otherwise, it may be reason to show the anomaly of purity, as suggested, and further, also show more evolutionarily demanded reasons for fluid and homosexual genders.