Your second point, RE: the continuous spectra idea, reminds me a fair amount of sexual orientation. When you think about it, like you and the author said, many, even most people in the west are still grappling with the mere idea of homosexuality. Suggesting bisexuality to even a moderately conservative person brings out anything from mild confusion to hostility. It's going to be a long road to convince the average person that there's a rainbow of sexuality, and everyone fits on a slightly different wavelength. But it's not because they're stupid - like you say, it's because there's a probably natural propensity for humans to organize things into neat patterns and discrete points, and have a hard time with fuzzy gradients. Perhaps its related to the ability to think abstractly? A strong abstract thinker can consider someone who isn't 100% heterosexual but has purely hetero relations, while a weaker one might only see the person purely in terms of their sexual actions and not their hypothetical place on the sexual spectrum. Excuse the digression, there's always a lot of overlap between the ideas of sex and orientation! Very interesting.
Exactly what I was getting at, and actually what I was basing the assumption on. As you may be aware, the Kinsey scale (which I don't agree with 100%, but it serves well as an example) describes this situation. In looking it up again now, I was drawn to a particular line from Kinsey: Unfortunately for humanity, continuums are not really very practical or intuitive (it would seem), and so I think we try to make do with approximations of reality. It's like trying to categorise certain music into genres. Sure you could call that one song "Nu Post garage-hop chillstep", but then the entire idea of classification starts to lose its value, as you aren't creating much more order than there was before. (I don't think this metaphor applies perfectly to sexuality though, but the idea is there) P.S. I like the idea of the different levels of abstract thinking because it infers that there is a continuous spectrum of understanding OF a continuous spectrum. Anyway, rambling again, I should go to sleep.The living world is a continuum in each and every one of its aspects.