Hi dmoose, your handle looks familiar to me. The non-glib answer is that we should giver some very serious consideration to the possibility that language either functions like, or possibly is the same as, Jung's collective unconscious: the organically created repository of all of humankind's cognition and reason, accumulated over vasts periods of time, deposited by billions of humans.

My way of "giving this serious attention" is through pre-registered, falsifiable, repeatable, experimentation, which anyone can look up on osf.io because I use my real name. I'll bet you that non of the randos in this thread do as much.

To all of the randos: unless you have data... it is just an opinion.

I don't disagree with your premise, but I'd argue that saying "there are no original ideas" in the context of a discussion of plagiarism is needlessly reductive. Even though I think I mostly agree with the author here, I think there are legitimate counterarguments that can be made; equating all of the ways someone can cite or build upon an idea with copying something word-for-word and claiming it's your own is not one of them though.