There’s a bundle of stuff about memes to sift through. There’s already a scholarly journal on memetics (the study of memes). Anyway, starting at the beginning, Richard Dawkins was the bloke who first started the meme meme rolling. He talked about them in his book The Selfish Gene, but in his next book The Blind Watchmaker, he defines a meme as
“[A] pattern of information that can thrive only in brains or the artificially manufactured products of brains, books, computers, [etc.]. [These replicators] can propagate themselves from brain to brain, from brain to book, from book to brain, from brain to computer [etc.]. As they propagate they can change – mutate. These mutants may be able to exert a kind of influence that affects their own likelihood of being propagated.”
Examples of memes are: tunes, ideas, catch-phrases, clothes fashions and ways of making pots or building arches.
And memes propagate like this:
Just as genes propagate themselves in the gene pool by leaping from body to body via sperm or eggs, so memes propagate themselves in the meme pool by leaping from brain to brain via a process which, in the broad sense, can be called imitation. If a scientist hears or reads about a good idea, he passes it onto his colleagues and students. He mentions it in his articles and his lectures. If the idea catches on, it can be said to propagate itself, spreading from brain to brain.
It’s quite a seductive idea – the notion that ideas propagate virally – but like a lot of seductive ideas, it seems to verge on the wishy-washy. Now, I’ve got some understanding of evolutionary theory, but I’m no great biologist. So to be clear about the terms and about how memes propagated themselves, I looked up what replicators are.