A woman is not defined by having a vagina. She is defined by having 2 X chromosomes, and her anatomy will normally develop into female anatomy.
You can generally tell a male from a female by looking at them. We dont need to know if they have a penis or a vagina, you can "generally" just look at a person and know.
Yes, there are some women who develop more masculine traits, and some men who develop more feminine traits, but in each case, you can tell, unless they have been surgically or hormone therapy altered.
Yes, there are instances where the two cross, but it is rare.
Yes, there are some people who believe that were born different than how they feel. Those things happen, but in almost all situations, you know what a man or a woman is.
You guys are trying to blur the line between male and female...for what? So, if a woman calls herself a woman, are you going to argue with her and demonize her for it? Are you going to challenge her on her own sex? If I tell you I'm a man, are you going to tell me I'm not? I know I'm a man, and nobody can tell me I'm not. I have xy chromosomes, hairy chest, masculine features and male genitalia, therefore I'm a man.
I'm curious..do you have kids? When you take then to the doctor and have to fill out the questionnaire, do you list them as male or female? If you do, how do you know? How does the doctor know how to treat them?
You know because biology tells us these things.