This just shows how pseudo-science reflects the prejudices of the dominant culture in society. 500 years ago atheism would have been viewed as a mental illness and people were burned at the stake for it. 200 years ago, being into S&M was viewed as a depraved mental illness. 100 years ago being homosexual was viewed the same way. None of these judgements had anything to do with mental health/illness, science, or facts, it was just a bunch of prudish prejudiced quacks masquerading as "scientists".
You can test someone's sexuality easily without them having to have sex - stick a copy of "Playboy" on one side of their bed, and "Gay Times" on the other, then see which one they jerk off to. By your logic, virgins have no sexual preference, even if they jerk off 5 times a day to porn videos.
So explain attraction to women from taboo religions, races, social classes etc? In the Deep South under slavery, lots of white slave masters f*cked their black slave women. Were they conditioned to find black women attractive, in an environment when they were widely viewed as subhuman? Some Nazi guards fucked Jewish concentration camp girls too. Also your logic suggests that without any active conditioning, men wouldn't find women attractive.
If someone has never got aroused by someone of the same (or opposite) sex, despite living for decades, I think it's pretty clear they are either 100% straight or 100% gay.
Is it strictly a physical attraction we are talking about? Hell, I'd much rather spend my time with men, but that isn't to say that I find another man's asshole in the slightest bit appealing.
Here's another wrench ... What's attractive has and will continue to change drastically ... Just leaf through a historical stack of playboys starting with 1960. Many faggots are narccistic, perverts hoping that their assholes will soon be accepted on the centerfold.
<i>Are you talking sexual inclination or sexual behaviour?</i> --->Inclination is sufficient enough to determine a person's sexual orientation. <i>Well Rearden why is that a surprise? Most studies put bisexual/bicurious people at numbers near that. 5% gay, 15% bi/bicurious would not surprise me at all. Of course the vast majority of those will be somewhat or fully in the closet, adopting the "wide stance" and checking out gay porn on the sly while their wife wonders what's wrong.</i> --->I guess because I have no interest in the hairy man-ass, I assumed other straight acting guys weren't interested in it either. Perhaps not. <i> I will never get married, but in the event that I ever settle down seriously with a woman... I'd also like equal recognition for visa/residency rights as married couples.</i> --->Does this mean you're into Eastern European chicks too? I knew you were a man of refined tastes!
If any of you lived in a city with a lot of gays or had friends who were gay - you would know that many gays were once straight. Then they sort of decided to by gay. And, sometimes they even go back to straight. At best "gayness" is a spectrum. I suspect there are few gays who were born gay. But, I suspect there are many more who made a choice or were molested into the choice. Most of the people I knew in college who became gay - were people who chose to be gay. Some were converted to being gay over years and some overnight. I remember a girl I knew being told by a friend of my that he was leaving her because he hooked up with a guy and liked it. But, I knew other guys who could not make up their minds for half a decade. My girlfriend lived in house full of lesbians. Those girls were switch hitters. I bet half of that group is married with kids now.