Except that I am not saying that we cannot know if anything is real. If you think I am, then you have misunderstood my position.
Perhaps I have. That remains to be seen
Categories are real and useful tools that help us to understand reality.
But they're not reality itself, and reality trumps any categorisation scheme we can come up with.
Okay... except these are not invented from nothing categories we're talking about, which we're trying to force things into. This isn't a cluster algorithm we're talking about. This is an observation of thousands of years and millions of species. Sex is one of the LEAST flexible elements in the kingdom animalia.
Your insistence that sex (or gender, or whatever) is strictly dichotomous and that all individuals can and must fit into one and only one of two and only two categories, is simply wrong - that is, it doesn't conform with the observed reality.
Gender is, in my opinion, utter balderdash. Gender is a socially constructed set of constraints, which have been tied to sex for most of our history.
Sex, however, is strictly dichotomous in humans, as it is in all other mammals, and the overwhelming majority of vertebrates. And given individual within a species can only be one or the other - but at no point have I suggested that this is always easy to determine.
If you wish to prove me wrong, all you need to do is find an example of a mammal which has a reproductive anatomy that has evolved to produce a sperg. Alternatively, you can produce an example of a mammal which has a reproductive anatomy that has evolved to produce a third gamete which is neither an egg nor a sperm. That's all that is required in order to prove that sex is not binary in mammals. Nothing more... but also nothing less.
Because the observed reality is that mammals are EITHER male OR female. They are never BOTH, nor are they ever SOMETHING ELSE. While it is incredibly easy to discern the sex of most mammals, there are some individual specimens that have disorders of development that make the expression of their sex-related characteristics ambiguous or confusing. But it remains true of observed reality that no mammal has a reproductive system that has evolved to produce a blended gamete or a third type of gamete.
Look, let's make a really bad analogy. Let's say I give you a really long decimal number, with thousands of decimal positions included. If that number is 3.1212121212121212 it's pretty easy for you to determine that it's a rational number. But I could give you a number that has a decimal component that is 50 spaces long before it repeats. It might be difficult for you to discern that it is a rational number... but it is still a rational number. By definition it is a rational number. On the other hand... you could stare at pi for every second of the rest of your life and it's not going to repeat. It is by definition an irrational number.
Just because it's difficult to determine whether a really long number is rational or irrational doesn't mean that it is both rational and irrational, and it certainly doesn't mean that it's neither.
It's not very wrong; The vast majority of humans do indeed fit easily into that dichotomy. But to demand or claim that every last single human does, for any given definition (and there are dozens of definitions, each useful in different ways and different contexts) is simply to make a demonstrably false claim.
There are a lot of definitions that people have crafted in order to support whatever pet beliefs they hold. There is also, however, a consistent and well-supported scientific definition that holds true across all known sexually reproducing species. Why should I be bothered with someone's made-to-fit narrative definition?
Not every human (or mammal) fits EASILY into the biological definition of male and female... but none fall outside of those definition. I never said every case was easy, and in fact I'm quite aware that some specific cases are more difficult to determine.
I once again invite you to present any single counterexample of a mammalian reproductive anatomy that has evolved to produce a sperg, or a mammalian reproductive anatomy that has evolved to produce a third type of gamete.
Let me remind you of the definition I am using:
Males are those members of a species who are of the reproductive phenotype evolved to produce and deliver small gametes. Females are those members of a species who are of the reproductive phenotype evolved to produce and deliver large gametes.
This definition does not imply that any given individual within the species actually produces those gametes, only that they are of that reproductive phenotype. It doesn't even imply that every member of a sex has every single component of a given phenotype. What it implies is that there is not a third phenotype, nor is there a third gamete. There is not an in-between phenotype, because there is not an in-between gamete. The definition doesn't demand strict conformity, and it doesn't rule out developmental disorders, deformities, anomalies, or mutations. The definition doesn't imply that it is always easy to tell.
Reality (particularly in biology) is under no obligation to be a neat or as simple as we would like it to be. Your desire to have a simple model is not a sufficient reason to declare that your simple model is an exact match for reality.
Reality is under no obligation to do anything, sure. But reality is supported by the definition that evolutionary biologists use for sex... and reality is NOT supported by any of the other definitions that have been vaguely hinted at without actually being supplied in this thread. And reality certainly seems to be better explained by the definition I've provided than by any of the non-definitions and hand-waving "it's complicated" that have so far been presented.
But by all means, if you think my definition is wrong, please provide a counterexample. Any mammal with a thirds type of reproductive system, evolved for a third type of gamete is sufficient.
That's not solipsism, nor is it post modernism. Those are just insulting labels you're sticking on your opponents to avoid the risk inherent in thinking about what they're actually saying, which could lead to disastrous consequences such as your being forced to recognise that you are not one hundred percent correct about everything.
"Everything is made up, you can't actually tell what's real" is solipsism and/or post-modernism. And at present, it's an appropriate description of the approach that Jaryn and you have put forth. I've given a lot of thought to the definition that I have adopted. This is not my field of expertise, but it certainly seems to be the definition accepted and used by evolutionary biologists. The only biologists I've seen who fall back on "oh sex is super complicated, you just totally can't tell" approaches are those who disingenuously use disorders of sexual development as a magical gotcha in their quest to insist that gender identity is just as real and objective as sex. They obfuscate sex, they obscure reality in order to make everything seem squishy... all to reach support their errant conclusion that a person's subjective internal gender identity is just as impactful as the observable reality of material sex.