What's not so obvious is they also behave as the basis for a Darwinian process
I had occasion to look up the number of books that had been published recently containing the word meme in the title and it's more than 20. I originally, in the last chapter of the first edition of 'The Selfish Gene’, coined the word meme really as a kind of afterthought, ah, because I was trying to illustrate the point that natural selection, the Darwinian process, which I think is universal and probably underpins life anywhere in the universe - if there's life elsewhere in the universe - requires a self-replicating entity as its base. On this planet, that self-replicating entity is pretty much always DNA, sometimes RNA in a few viruses. I wanted to make the point that it doesn't have to be DNA and if we were to fly to other planets, if we find life, as I suspect we would, somewhere, I would bet my shirt on there being something a bit like DNA. Something high fidelity, self-replicating code which is capable of not only making exact copies of itself with occasional flaws, but also capable of manipulating the world, something we would call phenotypes on this planet, manipulating the world in such a way to increase its own probability of being copied into future generations of that code. Now, other molecules with the same properties as DNA could do that, but I wanted to find a radically different example that people might understand. I could have used computer viruses. I don't think they'd even been invented in 1976, or perhaps I didn't know about them if they had, so I used cultural replicators. Things that spread through human culture. Things like tunes, clothes fashions, speech fashions, habits of speech, actually words themselves, anything which is an accurately copied piece of information which goes down along many, many generations with occasional changes. So, something like clothes fashions is a very good example. Crazes at school among children. Playground crazes for particular kinds of toys, particular games, they spread through a school like a measles epidemic. And then they die away like a measles epidemic and they may then jump to another school. Somebody's sister goes to another school and initiates the same epidemic of memes.
I wanted to make the point that it doesn't have to be DNA and that's surely true and there's lots and lots of examples of cultural replicators that behave just like DNA. What's not so obvious is they also behave as the basis for a Darwinian process, Darwinian survival value. That's a different question. Do some memes survive better than others? If they do then we have something like a Darwinian process. Do they actually build phenotypes for themselves in the way that DNA does? I mean, separate genes don't do anything much, genes collaborate together, collude together in enormous numbers to build individual bodies like whales and giraffes and kangaroos and humans. Could there be something similar to that in memes? Could there be meme complexes, and I suggested that perhaps religions might be meme complexes that survive because they're mutually compatible with each other, they go well together in the same way as, um, carnivore genes go together well with other carnivore genes and herbivore genes go well with other herbivore genes and I think it's a fruitful idea. Others have developed it, and had before, indeed, not under that name, many have done so and are doing so under the name meme. I think particularly of Dan Dennett, Susan Blackmore and various other people.
The word meme has started to have, in sort of internet circles, a particular meaning which is a subset of the correct meaning. A lot of people think it means…I think they think it means a sort of a picture or video which goes viral. And the going viral is entirely in accord with my original definition, in fact I used the analogy of a virus in 'The Selfish Gene’, but I think some people, some young people perhaps, think that a meme is a photograph spreading around the internet, and that's just one example along with perhaps an idea in a religion, along with a tune that people whistle in the streets and other people pick up, along with a fashion in headgear or footwear or something of that sort.