Someone who can participate in a pregnancy but cannot be pregnant.
That's a very poor explanation.
I could participate in a pregnancy. As far as I know, I'm still fertile.
I've not had potentially fertile sex in well over 30 years. I'm 63, unlikely to change my ways, but I qualify as "can participate in a pregnancy".
And furthermore, I was pregnant back in the day. Only once, my then girlfriend and I stopped using any version of the rhythm method after we got pregnant. But yeah, we'd made a baby together. We were both pregnant.
Tom
It's not an explanation. It's a definition: pick any given person who can be pregnant. There is a fixed population of people who can make that person pregnant.
From that set of people. find every person that they can make pregnant...
Repeat that process until the sets don't change.
You now have two populations relative to your selected "Eve": pregnancy theoretic males and pregnancy theoretic females. It's not ambiguous in the least: It is a fixed non-arbitrary convergent set with a fixed relationship to an admittedly arbitrary "Eve", though you can just use any given volunteer as a "Eve". This set is going to be mostly identical for any given selected "Eve" of a given species, assuming that individual can be made pregnant at all.
You can even start with a set of them, or even all people you care to look at. Then at the end to filter the set, you empty it and reselect from all persons using your discovered "pregnancy theoretic males".
As such "the set of those who cannot be made pregnant" is "a well defined set" under the definition "all people, of the set of all people, for whom are excluded when, following selection of all pregnancy theoretic males, are excluded from the subsequent selection of pregnancy theoretic females".
Did you miss "but cannot be pregnant"?
Honestly, though you're right. "Cannot be pregnant" is sloppy. That doesn't make someone pregnancy theoretic male since a pregnancy theoretic male can, in theory potentially also become pregnant. It would be a miracle of absurd proportions to have someone who has both gonads, both of which are functional in that way.
In that case they aren't not just "pregnancy theoretic male"; they're both.
It'll probably require the turkey baster though to get the job done for one or the other capability though...
This does imply a third category in "non-pregnancy-theoretic", and two/three meta-categories "not pregnancy theoretic male" and "not pregnancy theoretic female" (and I suppose "is pregnancy theoretic").These are mostly unimportant here, but become very important considering segregation of spaces for various, socially justifiable intents.
The idea is that we pick a representative group.
I create this distinction for only one reason: being pregnancy theoretic male is being proposed to carry a burden hopefully just as onerous as the risk foisted upon "pregnancy theoretic females" merely for existing as humans and liking the occasional shag, and being wired up in such a way as to make doing so as likely as possible to be "irresponsible".
This is to say, by remaining so in society, you natively pose a risk of being a parent, no matter what you want. Once you put it in someone else's body, it's in their body, not yours. No longer your decision.
This means BEFORE you are putting it in someone else's body,
there's a responsibility to have already done the work to make sure there's no risk to you or them or the possible child in the case you don't want to be a parent, or stay with the other parent for longer than a quick shag.
If you don't want the responsibility to have already done the work for that, get snipped.