Over in the Great Debate, I see you're talking about whether "vagina" is a proper word for formal discourse, i.e., the Wisconsin legislature. As a medical term, I agree with the consensus there that it is a proper term. It could even be a required term for certain kinds of legislation. Penal codes, for example, often define rape as any penetration of the vagina without consent. This is to change the law from older definitions, when there had to be "forcible" or "violent" penetration, or possibly even ejaculation. Some states also want to make it clear that it's rape even when the penetration is not with a penis, but with a finger or even a pencil, for example. But for penetration with a pencil to make sense as rape, obviously it has to be penetration of the vagina, not, say, the shoulder. Stabbing someone in the shoulder is battery or assault, not rape.
But you're also discussing whether abortion is rape, and the legislator (legislatrix?) kind of made an allusion to abortion restrictions being rape. Let me explain.
The legislator's remarks first. I haven't read the legislation, but a lot of states, notably Virginia, are requiring ultrasounds before abortions. Some have said this requirement, if not necessary for the abortion, is rape. I don't agree with them, but let me explain their thinking: Most fathers have probably attended an obstetric ultrasound at 16 weeks gestation. At 16 weeks, the woman is showing, and the doctor or tech uses extra-sticky hair gel on her abdomen and a rather flat ultrasound wand, kind of a square hockey puck. But early in a pregnancy, when most abortions take place, the ultrasound has be to internal. The wand goes in the vagina and is the shape of a curling iron, except domed at the end, so like a very large eraser-end of a pencil (can't remember the length, but between 1" and 2" in diameter). As these ultrasounds are not always medically necessary for the abortion, and involve vaginal penetration, some people analogize them to rape.
A kind of historical pro-life argument next: Historically, abortion has been an assault. "Safe" abortion is relatively new. I can't keep the statistics in my head, but certainly certain kinds of abortion are still less safe than carrying a pregnancy to term. There is also a line of thinking that because abortion is per se evil, no woman can really consent to it. Add to these understandings the fact that abortion necessarily deals with women's sexuality, and usually deals with their vaginas, and you come to the thinking that abortion is a form of sexual assault or rape. Not the "traditional" rape, but in a metaphysical or moral sense.
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