"The paradox and contradiction that is made apparent by these anecdotes defines much of the art of the last 50 years; art that has found itself by questioning authorship, authenticity and identity. It’s a questioning that ranges across many issues: the authority and meaning of the signature; the use of found source material as copy or theft; the adoption of a strategy of simulation within the conception of the work; a re-questioning in those terms of the status and usefulness of the Duchampian readymade that itself refers directly, through the act of nomination, to the role of the signature; the definition of the copy in terms of the relationship to a primary source that has been lifted to new use, the repetition of such an act, or even the representation of the act of repetition as a form of copy."

— from “‘This is Not By Me’: Andy Warhol and the Question of Authorship” by Andrew Wilson