Harper's magazine, April 2007, page 4
This letter to the editor addresses the boundary between plagiarism and creativity.
Creativity requires borrowing from the work of others, but one should give them credit.
An earlier essay in Harper’s Magazine does a good job of describing the importance of “remixing” to creativity.
We cannot create without drawing on the work of others.
The essay, however, used a sentence from Lessig's own work without giving him credit. This is very close to plagiarism.
If you use another’s words verbatim, you should not have to get permission first, but you should give him or her credit.