“Perhaps the Russians have done the right thing, after all, in abolishing copyright. It is well known that conscious and unconscious appropriation, borrowing, adapting, plagiarizing, and plain stealing are variously, and always have been, part and parcel of the process of artistic creation. The attempt to make sense out of copyright reaches its limit in folk song. For here is the illustration par excellence of the law of Plagiarism. The folk song is, by definition and, as far as we can tell, by reality, entirely a product of plagiarism.”

And I said "Right."
Spoken on the Track "The Story of Reuben Clamzo" on the album One Night.

Message on mimeographed copies of lyrics distributed to fans in the 1930s, as quoted by Pete Seeger in an NPR interview "Pete Seeger remembers Woody" (1996)
Context: This song is Copyrighted in U. S., under Seal of Copyright #154085, for a period of 28 years, and anybody caught singin it without our permission, will be mighty good friends of ours, cause we don't give a darn. Publish it. Write it. Sing it. Swing to it. Yodel it. We wrote it, that's all we wanted to do.

Source: Letters from the Earth: Uncensored Writings
Source: Mark Twain's Notebook (1935), p. 381

Quoted in Alva Johnston's The Legendary Mizners (1953, Farrar Straus and Young, New York, chapter 4, p 66) and Bartlett's, 1992, p. 631.
Also quoted as If you copy from one author, it's plagiarism. If you copy from two, it's research by Stuart B. McIver in Dreamers, Schemers and Scalawags.
Epigrams

Source: The City of Dreaming Books

As a performing artist, he will pride himself on timing and other techniques designed to keep the audience in his control [...] his respect for genuine folklore reminds him that these changes, and these techniques, may give the audience a false picture of folk music.
"The Singer of Folk Songs and His Conscience", Western Folklore 14:3, (July 1955), p. 170–173

Remarks by the President on Immigration -- Chicago, IL (November 25, 2014) http://www.whitehouse.gov/the-press-office/2014/11/25/remarks-president-immigration-chicago-il
2014

Free Culture (2004)
Context: Common sense is with the copyright warriors because the debate so far has been framed at the extremes — as a grand either/or: either property or anarchy, either total control or artists won't be paid. If that really is the choice, then the warriors should win.
The mistake here is the error of the excluded middle. There are extremes in this debate, but the extremes are not all that there is. There are those who believe in maximal copyright — "All Rights Reserved" — and those who reject copyright — "No Rights Reserved." The "All Rights Reserved" sorts believe that you should ask permission before you "use" a copyrighted work in any way. The "No Rights Reserved" sorts believe you should be able to do with content as you wish, regardless of whether you have permission or not.... What's needed is a way to say something in the middle — neither "all rights reserved" nor "no rights reserved" but "some rights reserved" — and thus a way to respect copyrights but enable creators to free content as they see fit. In other words, we need a way to restore a set of freedoms that we could just take for granted before.