Disclaimer: I should say I am not a psychologist or biologist, though I have a few college level courses in the prior which probably color my view. In addition, I am not sexually a homosexual and have no personal experience with that aspect of it, though it piques my intellectual interest. Also, I am European (this is apparently a synonym to many).
Question: Do you tend to support a psychological or a biological explanation to why some people are homosexuals? Do you have a "pure" or a "mixed" view of the two, and why?
My opinion: I tend to support the psychological explanation of sexuality due to it being more parsimonious. Being "born" a homosexual doesn't immediately ring clear as a biological explanation requires a number of a priori assumptions of future state of the social environment as one grows up. Two people of the same sex cannot biologically reproduce and thus face extinction. Becoming a homosexual through the psychosocial environment is to me a simpler explanation as this would imply it being either a learned behavior, which may account for homosexual couples having a higher probability of raising a homosexual child, or as a response to other environmental factors such as sexual competition.
I'll stop explaining here and rather see where the discussion goes off to.
(Two notes to add: I don't think homosexuality should be treated even if it is "treatable". It is no more a condition than preferring beer over vodka. Also, I tend to support a twin explanation of both inherited and environmental causes, though with the latter overwhelmingly more explanatory, i.e. 90%)
For me it's a blend of biological and society. But by biological, I do not mean genetic. However womb environment and mother's behaviours during gestation I can see having an effect.
Within a decade or two, when more serious research has been completed on this topic, I think we'll find that as with diseases (not saying they're the same obviously) there is a genetic component, a gestational component, and an environmental/sociological component.
But we must be careful what we wish for (in the case of those siding with the genetic aspect). As my lesbian sister rightly points out... if we find precise biological causes, creepy religious homophobic scientists will instantly be searching for drugs to reverse the homosexual 'effect'. My sister, after years and years of honest self evaluation, has come to the conclusion that her lesbian lifestyle is environmental, even though her sexual interests began as lesbian, from puberty onward. I was treated very harshly by my father, my little sister was always the little white lamb of the family (for the few years it was one), and she constantly felt pain over seeing my mistreatment.
As for people switching... people do switch back and forth... females apparently much more so than males... which in itself is an interesting topic of research, not sufficiently researched yet.
In my experience of being a gay man I knew I didn't "like" girls for as long as I can remember, even before I knew the labels "Gay", "Bi" or "Lesbian". I would probably go with the biological theory simply because I was not raised around any gay or lesbian people and so couldn't have "Learned" my sexuality from those I was around.
I'm not entirely sure what you mean by the statement you didn't "like" girls for as long as you can remember. Gay males seem to have an affinity for females. Or did you mean to say you didn't find yourself sexually attracted to girls?