An analogy sometimes used in copyright law, to the effect that an infinite number of monkeys, left in front of typewriters for an infinite period of time, would eventually type out Hamlet (or alternately the entire works of Shakespeare). In such an event, it is usually suggested that the work would not infringe Shakespeare’s copyright or that the monkeys would enjoy copyright in their work.
Although initially appealing, the analogy is a legal nonsense. First, Shakespeare has been dead for hundreds of years—since copyright in a work endures only for life plus seventy years, it is self-evident that Shakespeare’s works are in the public domain and copyright could not be infringed, either by intentional retyping or random simian hammering. Second, in principle, (and not withstanding any protests from animal rights campaigners) the random typings of monkeys are so devoid of aesthetic and literary intent, that whatever resulted, even Hamlet, would not likely be entitled to copyright. Third, how would one prove infringement (assuming the monkeys did have copyright) given the existence of an identical version of the work already in the public domain?
How the analogy came to be used (usually verbally) in copyright law is obscure, as indeed is the origin of the analogy. The mathematician Emil Borel, in a 1909 book on probability theory surmised that “dactylographic monkeys” left in front of a typewriter keyboard long enough would eventually type every book in the French National Library. Later the physicist Arthur Eddington suggested in The Nature of the Physical World: The Gifford Lectures (Macmillan 1929) “If an army of monkeys were strumming on typewriters they might write all the books in the British Museum.”
This scale of this challenge has in theory reduced since the library of the British Museum (then the British National Library) has been since been transferred to a separate institution, the British Library (but more books have been published.) However, the origin of the migration of the work recreated by the monkeys from assorted libraries to either Hamlet or all of Shakespeare’s works is, as yet, unknown. What is known is that in 2003, scientists from the University of Plymouth working at Paignton Zoo in Devon, England, decided to practically test the theorem by leaving a computer keyboard in the enclosure of six Sulawesi Crested Macaques for a month. At the end of this period the monkeys had produced five pages consisting mostly of the letter S, had attacked the keyboard with a stone, and then urinated and defecated on it. It should be recognized though, that the experiment did not disprove the theorem; rather it was inconclusive due to the failure to use sufficient time, and indeed the use of macaques—maybe they should have used more-intelligent chimps—although technically chimps are apes rather than monkeys.