
I am still having a hard time wrapping my head around that we have all been fooled about sex all allong as said by Luce Irigaray.
The reason that we don't specify people by hair color or eye color or height because to each person they have the same (or similar) functions.
It is true it can be said the male parts and female parts have similar functions but the have different roles to meet the same end. Creating the next generation of life seems to be the ultimate goal of all biological beings - mammal, amphibian, insect etc.
There has never been a child born from the union of two men or two women as far as I know (at least not without the help from science)
I would say people (or puppies) who have both would base their sexual identity on which organs function. (Why else would the vet call Jessica's dog a girl even though she has male dangly parts?)
It is true there is a third category of sex based on asexual reproduction. - there aren't girl sponges and boy sponges (sorry Spongebob)
These "its" in humans show genetic mutation not a third human sex. It is not common enough to call them a completely third category. Usually (if I am not mistaken) in the case of hermaphrodites they only have one set of sexual organs that function correctly.
Maybe I am just completely immersed in the dogma that is the Dead Men of Europe's perspective but it seems to make logical sense.