The Meme Machine

54 THE MEME MACHINE
which is a sufficiently long sequence of nucleotides to provide the instructions
for building one protein – with a start symbol and a stop symbol. Neither of
these is necessarily passed on intact in sexual reproduction and neither
corresponds with what we think of as the gene ‘for’ something. DNA provides
instructions for protein synthesis and it is a long way from there to having blue
or brown eyes, finding men more sexy than women, or having a flair for music.
Yet it is these effects of genes that natural selection gets to work on. So what is
the unit of the gene?
Perhaps there is no final answer. One useful suggestion is that a gene is
hereditary information that lasts long enough to be subject to the relevant
selection pressures. A sequence of DNA that is too short is meaningless – it
lasts almost indefinitely, being passed on identically from generation to
generation but taking part in countless different kinds of protein synthesis and
countless different phenotypic effects. A sequence that is too long does not
survive through enough generations to be selected for or against. So some
intermediate length has to be chosen, and even this varies with the strength of
the selection pressure (see Dawkins 1976; Williams 1966).
This intrinsic uncertainty about just what to count as a gene has not impeded
progress in genetics and biology. It has not made people say, ‘We cannot decide
what the unit of the gene is so let’s abandon genetics, biology and evolution’.
These sciences all work by using whatever unit they find most helpful for what
they are doing at the time.
The same logic applies in memetics. Dennett (1995) defines the units of
memes as ‘the smallest elements that replicate themselves with reliability and
fecundity.” (p. 344). A blob of pink paint is too small a unit for memetic
selection pressures to apply – to be enjoyed or disliked, photographed or thrown
away. A whole gallery of paintings is too large. The single painting is the
natural unit for most of us and that is why we remember Van Gogh’s Sunflowers
or buy postcards of Edvard Munch’s The Scream. Styles of painting, such as
impressionism or cubism, can also be copied and therefore count as memes, but
can hardly be divided up into units. A single word is too short to copyright and
an entire library too long, but we can and do copyright anything from a clever
advertising jingle to a 100 000-word book. Any of these can count as memes –
there is no right answer to the question – ‘What really is the unit of the meme’.
I might have argued that four notes is too short to be a meme but everyone’s
favourite example shows I am wrong. If a musical genius picks on just the right
four notes, starts a wonderful symphony with them and has the luck to have his