Human nature. It’s what supposedly prevents us from having nice things. Its foundation is the habits of humans tens of thousands of years ago that of course we know everything about even without references. It usually assumes that we are all some monolithic entity that interestingly shares the culture of the person making the argument. When it’s not, it’s used to justify stereotyping people into neat little boxes so we don’t have to deal with those icky things called women’s rights or minority rights. And it’s all true because it’s so obvious. Well, that’s not how the world works.
First off, you can’t analyze anything properly when your conclusion is decided from the outset. Conclusions are supposed to explain what occurred in your observation, and if it contradicts the facts, it’s wrong. When the opposite occurs instead, you end up overlooking or even dismissing facts that don’t agree with your conclusion. Evolutionary psychology which is often strongly influenced by the prejudices of the people “studying” it often vomits out godawful papers such as the infamous “girls like pink because it helps them gather berries”. Yes, it’s been brought up ten thousand times, but it’s a great example because one obvious fact shoots the theory to hell. Blueberries. And a whole bunch of other things, but like I said, it’s pretty much the bad science punching bag at this point (but it’s still benign compared to “rape is an adaptation“). Capitalist apologists love this form of pseudoscience too. They tell you it’s human nature to reject socialism because competition is the natural state of humanity (guess Marxists aren’t the only ones using a false consciousness argument) while ignoring all the times that humans have cooperated in history and it was of greater benefit to do so. Science itself wouldn’t be nearly as prolific as it is without peer review and sharing ideas.
Most importantly, human “nature” conveniently ignores that little thing called free will. We are not machines. We are conscious beings. We can look at ourselves and think about whether we are hurting ourselves and the people around us through the way we act. We can critically analyze situations and defeat people’s expectations. So many men for instance go on and on about how they can’t control themselves sexually harassing women because it’s a male instinct to ogle them or worse. Well if that’s the case then I am no man (I’m androgynous, but that’s beside the point). Even if this supposed “instinct” existed, you don’t have to listen to it!
So in conclusion, human nature is bullshit. It’s intellectually and socially lazy with no grounding in solid facts. I wish people would stop using this logical fallacy, but that would require us to be aware of our prejudices. And we can be, because we’re, well, human.