+The _Unit of Caring_ author continues:
+
+> If your definition of a 'woman' is one where trans people will be their preferred gender once the tech catches up, then I think you should probably reflect on what actually changes about anyone's lived experience on that magic day when our cyborgs hit your threshold. And if it isn't, then you're stuck asserting that if a woman is cell-for-cell identical to me then she still might not be a 'biological woman'. That's a sign that this isn't actually about biology.
+
+I would rather say that's a sign that we're facing an instance of the [Sorites paradox](https://plato.stanford.edu/entries/sorites-paradox/), the ancient challenge to applying discrete categories to a continuous world. If one grain of sand doesn't make a heap (the argument goes), and the addition of one more grain of sand can't change whether something is a heap, then we can conclude from [the principle of mathematical induction](https://en.wikipedia.org/wiki/Mathematical_induction) that no number _n_ ∈ ℕ of grains make a heap. (Or, alternatively, that the absence of any sand constitutes a ["heap of zero grains"](https://www.lesswrong.com/posts/nso8WXdjHLLHkJKhr/the-conscious-sorites-paradox).) Analogously, if a sufficiently small change in MtF transition outcome can't change whether someone is a woman, then we are seemingly forced to accept that either everyone is a woman or no one is.
+
+While the Sorites paradox is certainly an instructive exercise in the philosophy of language, its practical impact seems limited: most people find it more palatable to conclude that that the heap-ness is a somewhat fuzzy concept, rather than to concede that the argument isn't actually about the amount of sand in a location. And if you brought a single grain of sand when someone asked you for a heap, they probably wouldn't hesitate to say, "That's not what I meant by _heap_ in this context _and you know it_."
+
+> If that's the side of this question you come down on, then I encourage you to ask yourself why that trans women still doesn't count. I expect that whatever your answer, that's the real definition you’re using, not "biological".
+
+I definitely agree that this is a valuable thought experiment: in this limit of perfect physical transition technology, what possible reasons could there be to deny that trans women are women? Allow me to give a conditional answer.
+
+_If_ psychological sex differences aren't real, then there aren't any: _ex hypothesi_, the physiological differences between females and males are the only thing for the word _woman_ to attach to, and _ex hypothesi_, we know how to fix those.
+
+Alternatively, _if_ psychological sex differences _are_ a thing, _and_ transness is a brain intersex condition such that pre-transition trans women are _already_ psychologically female, then again, there aren't any: _ex hypothesi_ _&c._
+
+However, _if_ we should be so unlucky to live in a world in which psychological sex differences _are_ a thing _and_ most trans women are motivated to transition by [some _other_ reason](http://www.annelawrence.com/autogynephilia_&_MtF_typology.html) than already having female minds, then we face some subtleties: if our thought-experimental perfect transition tech doesn't edit minds, then we end up with a bunch of female-bodied people with a distribution of psychologies that isn't just not-identical to that of natal females, but is actually coming out of the _male_ distribution. Should such people be called women? Honestly, I lean towards _Yes_, but I can at least _see the argument_ of someone who preferred not to use the word that way.
+
+Wrapping up—
+
+> 3) What does this definition of 'woman' get you?
+
+It gets us a concept to refer to the set of adult human females. (Even if, again, we often also use the word _woman_ in a broader trans-inclusive sense; it's not uncommon for words to have both narrower and broader definitions which can be distinguished from context.)
+
+If the concept of _women_ in the narrow, trans-exclusionary sense is to be forbidden from polite Society, then people trying to make sense of their experiences will be forced to reinvent it, probably by means of obfuscatory neologisms ("assigned female at birth") coupled with the quietly indefatigable [wordless anticipation](https://www.lesswrong.com/posts/a7n8GdKiAZRX86T5A/making-beliefs-pay-rent-in-anticipated-experiences) that it's _somehow not a coincidence_ that cis women and trans men and a.f.a.b. nonbinary people get pregnant sometimes, but cis men and trans women and a.m.a.b. nonbinary people never do.