Two high school kids, seemingly not unintelligent, arguing by the catalog terminals in the public library of a small New England town with a healthy tax base. (Note: this is paraphrased, since I was trying to figure out what the hell they were talking about, rather than trying to remember what they were saying, but the gist of their conversation, I believe, remains intact.)
A: She wanted us to find something that’s common knowledge. What’s common knowledge?
B: Okay. You know how there’s entire books you can get that are online, that started out as, like, regular books?
B: And those are, like, ebooks?
B: And how there’s this massive nationwide effort to do that?
B: That’s common knowledge.
My guess is that the “she” they were talking about was their teacher. As for what appears to be a giant mental muddle of the nature of United States copyright law, the concept of the public domain, and how these apply to digital information—with, perhaps, a small trickle-down dose of the Google Print project thrown in for good measure—your despairing guess is as good as mine.