I am fascinated by this thread. I hope I do not ramble too much...
This discussion leads me to reflect on the individuality of perception. I think it is fair to say that none of us really understands at the internal level, that is, really can say they have shared the experience of being the other person. We may share external experiences, have similar reactions to those experiences, find we have similar or dissimilar likes adn dislikes, etc. But at the core of the question is whether you, I or anyone else on this site will ever truly know what it is to be the other, let alone what is internally feels like to be a genetic woman at the cellular, physiologic and neuropsychological level.
It is something similar to trying to explain in objective perceptual terms, not by analogy, what blue is or what the sound of an A (440 Hz) is or what sweet is. I don't want to delve into the hundreds, no, thousands of years of philosophical writing on the subject of epistemology but suffice it to say that it leads me to a very humble state of mind. I have to respect you and your perception as unique and deserving respect.
I am often prone to think that I "feel female" inside but in the next instant realize that I've never really been physiologically female. How do I know it, then?
I think we do take our cues in large part from the way we are hard wired to interact with one another, integrate socially, begin to realize our preferences and behaviors are more consistent with one gender or the other. This is a substantial part but I have to propose a rather unscientific explanation--something like the the biblical "still quiet voice." Yes, I have this "voice" in a big way. I think most of us do although some are deaf to it. It is not really so unscientific--it is the unconscious, the ego, or maybe as simple as the hardwired circuits that allow our consciousness. I listen to this "voice" regularly during meditation practice. It is an interesting interplay that I can "watch" internally between my highly logical scientific side and this highly intuitive "voice." The best way I can describe it is a debate between these two archetypal mental essences that I can consciously internally mediate during meditation.
The intuitive "voice" knows it is largely feminine but I cannot understand exactly how. The logical side has come to understand this as fact but acceptance without mechanism or proof was difficult. In the broader sense, the conscious "I" has come to accept the intuitive; what and how I feel as axiomatic--accepted as an obvious truth not needing external validation or proof.
I loved Terri's post describing how she will never know the life socialization and life experiences that most women enjoy from childhood through adulthood. Still she is confident of her greatest comfort living as a woman based on her experience doing just that. I admire her for being a great and mindful empiricist; a good scientist, an experimentalist.
When I was an adolescent, I had a difficult time dating initially, something symptomatic of my gender uncertainties. I found myself wondering what it felt like to be the woman in the relationship. I was pretty sure I was experiencing feeling more similar to that women experienced in relationships than what I understood was the typical experience of my male peers. Even at the sexual level, I found intense desire to know how it physically and emotionally felt to be a woman. That was a big insight for me.
So, for me, it boils down to something like the logic of the Turing test for evidence of intelligence. (Paraphrased: it is intelligent if you are convinced it is intelligent.) Commuted to gender: You are the gender you are convinced you are.
Axiomatic.
Steph