Robotics Reference
In-Depth Information
Researchers in the field of computer poetry made no significant concep-
tual breakthrough until Ray Kurzweil started his Cybernetic Poet project
in the mid-1980s. His program was based on a device called Markov
chains, named after the Russian mathematician Andrei Markov (1856-
1922). A Markov chain models the behaviour of a sequence of events,
whether they be successive words in a poem, successive notes in a piece
of music or any other type of event. If it knows how often one particu-
lar event follows another, a computer system can simulate a sequence in
which events follow each other with the prescribed frequency.
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Kurzweil's program modelled the writing styles of 20 classical and 16
contemporary poets. The program, known as the RKCP,
8
incorporates
a software module to avoid plagiarising the original poets on which the
Markov chain data has been based, by rejecting sequences of four or more
successive words that appear in any of the works of one of the original
poets. And RKCP's Markov modelling is not only based on sequences of
words found in the original poems, it is also based on the human poets'
word structures, their rhythm patterns and the overall structures of their
poems.
When generating a poem the program employs some heuristics de-
signed to give it creative intelligence. For example, when deciding which
word to write next, the program first determines a set of goals for that
word. One of these goals attempts to relate the next word to one or more
of the words already in the poem. Another goal is designed to choose a
word that is appropriate for its exact place in the poem. Yet another goal
encourages the selection of a word suitable for the particular human poet
whose style the program is trying to emulate.
The following poem, “A Wounded Deer Leaps Highest”, was writ-
ten by Ray Kurzweil's Cybernetic Poet after reading poems by Wendy
Dennis
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and Emily Dickinson.
A wounded deer leaps highest,
I've heard the daffodil
I've heard the flag to-day
I've heard the hunter tell;
'Tis but the ecstasy of death,
And then the brake is almost done,
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For a more detailed description of how Markov chains work, see the section “Markov Chains
in Music” later in this chapter.
8
Ray Kurzweil's Cybernetic Poet.
9
A poet employed by Ray Kurzweil.
