Jordan Peterson and others contend that SJWism is an outgrowth of postmodernism. I don’t know much about postmodernist philosophy, but if I understand right (and I’m pretty sure I don’t) it sort of says “Anything goes, categories are as arbitrary as their labels, everything is relative, etc.” It would make sense for SJWs to be an outgrowth of postmodernism, and maybe its roots can be traced there somehow, but I just don’t think that’s what’s going on in everyday terms.
I can’t fathom that SJWs are sitting around reading and getting inspired by philosophy, postmodern or otherwise. Even indirectly, through postmodernist thought leaders or publications or whatever, I find that linkage implausible.
Instead, I think the Occam’s Razor explanation is that the most puerile impulses related to equality, fairness, and self-determination are being indulged and in many cases rewarded, if not by wider institutions (e.g. humanities departments in universities) then in carefully curated echo chambers online. These are not the lofty values of equality or self-determination the 19th century American transcendentalists wrote about, but the infantile version of them that preschoolers throw tantrums over: He got a toy, so I should have a toy! I’m a tiger, not a little kid! Etc.
Let a preschooler keep throwing tantrums over the same things, and when he reaches college age he will be a ripened SJW. Am I omitting something by simplification?