Erasmus Darwin,
29 December 1804 – 26 August 1881
Today, Thursday, October 7th, is National Poetry Day [in the United Kingdom], a fact that once would have been of much interest to
scientists. In the 1700s several poems appeared that passed on a scientific message. The best known is The Loves
of the Plants, by Erasmus Darwin, who in 1791 set out in verse an account of
the sexual habits of the vegetable world. He used heroic couplets, in which the
rhyme pattern is AA, BB, CC and so on (for the sensitive plant, for example, he
wrote that "Weak with nice sense the chaste Mimosa stands,/ From each rude
touch withdraws her timid hands;/ Oft as light clouds o'erpass the summer
glade,/ Alarm'd she trembles at the moving shade"). Byron, a rather better
poet, liked the form ABABABCC and in his epic Don Juan even manages to squeeze
in a mention of Newton ("And this is the sole mortal who could grapple/
Since Adam, with a fall or with an apple.")
Overblown as Erasmus Darwin's verses might seem
nowadays, the point of poetry was pattern; to use a strict structure of rhythm
and rhyme as a framework for words of passion or pedantry that would become
fixed in a reader's brain. Robert Frost put it neatly when he wrote that
"Poetry without rules is like tennis without a net".
Poetry, in other words, is mathematics. It is close to a
particular branch of the subject known as combinatorics, the study of
permutations – of how one can arrange particular groups of objects, numbers or
letters according to stated laws. As early as 200 BC, writers on Sanskrit
poetry asked how many ways it is possible to arrange various sets of long and
short syllables, the building blocks of Sanskrit verse. A syllable is short,
with one beat, or long, with two. In how many ways can a metre of four
syllables be constructed? Four shorts or four longs have just one pattern for
each, while for three shorts and a long, or three longs and a short, there are
four (SSSL, SSLS, SLSS, and LSSS, for example). For two of each kind of
syllable, there are six possibilities. Do the sum for metres of one, two,
three, four and more and a mathematical pattern emerges. It is Pascal's
Triangle, the pyramid of numbers in which the series in the next line is given
by adding together adjacent pairs in the line above to generate 1, 1 1, 1 2 1,
1 3 3 1, 1 4 6 4 1, and so on.
As in
a great poem, hidden within that elegant structure are deeper truths that touch
on apparently unrelated things; on fractal patterns, on the theory of numbers,
on primes, and of complexities too deep to be accessible to mere mortals
untrained in the mathematical art. One useful property is that Pascal makes it
possible to ask in how many ways it is possible to arrange a group of objects,
be they footballers in a league, or lines in a poem.
The
French writer and amateur mathematician Raymond Queneau took advantage of that
in his 1961 book A Hundred Thousand Billion Poems. It consisted of a series of
10 sonnets of 14 lines, each with exactly the same structure of rhythm and
rhyme and with each line printed on separate strips of card that could be
rearranged. They are eccentric but engaging: one begins, in translation,
"The Parthenon horse looks nervous on the frieze,/ Since Elgin seems to
think the nose de trop,/ Just as the Turk is deeply mired in sleaze,/ The 're' in all
his songs came out as 'doh'".
Another
starts: "When all that's left is sorrow and disease,/ When undertakers
peer and say O-ho!/ The timid mutter into their goatees,/You hear your spouse
pay off the medico".
The lines are then reordered at random to generate new poems – to give,
according to the Law of Pascal, 10 to the 14 possible combinations. At 12 hours
a day, it would take around 300 million years to read them all (which is about
the time it took us to evolve from reptile to human).
And,
speaking of reptilian poets, it has just been announced that a cache of letters
from Philip Larkin to his mistress Monica Jones has been found (The Daily
Telegraph published
a selection last week). I look forward to reading more of them, for who can
afford to miss the writings of the man who produced the most genetical poem in
the English language? I quote the second verse, for his views on Mum and Dad in
the first are not suitable for the chaste Science page of this newspaper:
"Man hands on misery to man/ It deepens like a coastal shelf/ Get off as
quickly as you can/ And don't have any kids yourself". Happy Poetry Day!
By Steve Jones, professor of genetics at University College, London, U.K.
