It started as a throwaway notion in 1976, has spread steadily like a cult, and now looks set now to virally implant itself, permanently, into the language. Enter the meme, a metaphoric spin-off from the genetic explosion: the fundamental self-replicating unit of culture, or even thought. Classic examples include the latest hit boy-band melody; a popular new unprintable joke; the second coming of the platform shoe; or indeed the Y2K, er, scam.
Although slow-burning, the very idea of a meme has proved to be a successful bug, having spawned a growing academic field of "memetics" which its exponents, and impressionable journalists, now describe as a "science".
The word "meme" has appeared often enough in print for the Oxford word-crunchers to include it in last year's New English dictionary - which defines "meme", oddly enough, as a biological term, meaning "an element of a culture, or system of behaviour, that may be considered to be passed from one individual to another by non-genetic means, especially imitation".
Apart from precursor concepts such as "mnemones", the "meme" originally occurred to evolutionary theorist Richard Dawkins in the final pages of his influential best-seller, The Selfish Gene (1976). "Just as genes propagate themselves 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."
It's a catchy notion - the very idea of an idea, wrapped up in a neat word adapted from "gene" and linguistic terms such as "phoneme" (a perceptually distinct unit of sound). And in an increasingly free-market world, it's but a short step to see a Darwinian struggle going on between chunks of information within a global habitat of human minds - what meme-heads call the "ideosphere".
It is an interesting re-imagining of cultural evolution: in which "selfish memes", subjected to the Darwinian algorithm, mutate and increase in order and complexity: from farming methods and the wheel, to arches and suspension bridges; from abaci to silicon chips and mobile phones. The spin-off sweeteners for human organisms - either pragmatically (tools, technology); politically (as in such historically contagious memes as Thomas Paine's The Rights of Man); or in terms of emotional pleasure (from the Cork Hornpipe to Mozart's Requiem) - all ensure a meme's replicability, or popularity in human terms.
And just as mutually compatible genes ganged together symbiotically to form higher organisms, so memeticists argue, successful memes hooked up with other memes to form meme complexes, or "memeplexes": big self-contained accretions of ideologies which may provide fringe benefits to human communities - or indeed damage, in their most irrational excesses. Ultimately, such memeplexes exist only to ensure their own propagation.
Memeplexes commonly cited include Communism and indeed the ethos of vast corporate entities whose employees learn to say "we" when discussing the company, even in the pub.
Various forms of organised Christianity explicitly instruct their adherents to spread the faith - that is, to replicate it in the brains of others.
Other fervid memeplexes, such as Nazism or Scientology, include similar submemes for proselytising, often with frightening implications for dissenters.
Any robust memeplex has strong in-built defences against memetic attack. Memes for faith tend to discourage critical judgement; Freudians tend to psychoanalyse the unbeliever; and conspiracy theory memeplexes automatically dismiss lack of evidence as proof of how vast and effective the conspiracy actually is.
According to memeticists, one distinguishing characteristic of humanity is the almost addict-like facility for mimicking. We're wide open to all memes as children, they say. The memes then battle it out in our little minds until certain in-built-obsolescence memes, for example Santa, finally fall prey to a threshold in "cognitive dissonance".
Yet such a human aptitude for mimicry, even in adulthood, gives rise to high-fidelity replicability for the surviving memes, creating highly stable memeplexes like languages and accents, prejudices and traditions. Most children of Catholic parents, for example, remain Catholic, as indeed with Protestant families - a phenomenon often reinforced by sub-memes for mutual intolerance.
While more complex than an ant colony, the memeplexes of normative society create a very robust status quo. Look at polite society in 1930s Germany, cowed by the predominant, loud, adversarial Nazi memes, which locally at least, obliterated any memetic opposition. And despite the outcome of the second World War, it is virtually impossible to quarantine such memes. Nazi memes successfully evaded extinction. Similarly, the Roman Church will probably survive the vast proliferation of "scientific" memes since Galileo.
And "scientific" memes are very tenacious too: once you have accommodated them into your worldview, it is well-nigh impossible to shake them off.
Memeticists tend to be hard-wired with neo-Darwinist memes, and will probably remain so until the next, more attractive meme evolves to attempt to explain the dynamics of human intellect and culture.
As you go deeper and more gullibly into memetics, a whole ontological paradigm emerges in which ideas are seen as living organisms, which like viruses, "infect" and "parasitise" us, causing real physical changes in the wiring of our brains. It fetches up a paranoid mental tyranny of replicators, like tunes which replay themselves over and over in our heads, despite our best efforts to think of something else.
Our whole history as a species paints us as meme-facilitators - with our accelerating development of languages, scripts, printing presses, and the explosion of media technology - culminating in the information age. Indeed, the Internet may be the final stage of memetic evolution - a massive, decentred substrata for the Human Memome Project, which has transcended us, its original vectors; leaving us awash in an hyper-ecology of supermemes and information overload.
Never mind that memes have no identifiable substrata or structure, or indeed that memes are not perfect replicators (people, say, tend to pass on the gist, rather than the literal text, of a story). Despite the dubious analogy with the gene, academia is buying memetics big time. Memetics is now infiltrating cultural studies, media and communication theory, ethology (animal behaviour) and speculative fields such as evolutionary psychology, which worries about the origins of language, and indeed moral and altruistic behaviour.
Thump "meme" into any Net search engine, and headache your way through the entire libraries of congress being written on the subject, notably in the on-line Journal of Memetics, with its raging, tortuous controversies in "memetic engineering" and "population memeticists". Some writers fear that memetic evolution appears to be (oh, horror of horrors!) Lamarckian in nature; others that the "thought contagion" metaphor is retarding the progress of memetics.
The wonderful circularity of memetics has seen it take over from semiotics as the central, delirious cul-de-sac of post-modern discourse. Its more clap-happy supporters (visit the on-line Mimesis conference, or the Principia Cybernetica webpages) are often pranksters who claim memetics can help you start your own religion. Other apply it to business planning, corporate management, stock exchange markets, even computer models of artificial societies.
Just as we have always made anxious metaphors of ourselves and society from our dominant technologies, the meme meme, so to speak, ties in with the revival of social Darwinism in visions of capitalism; the infective metaphor of computer viruses; even the viral apocalypse of AIDS. Sometimes referred to as Cultural Virus Theory, memetics also chimes with William Burroughs's contention that language is a virus, probably from Venus.
Oxford University Press seems to have bought into it too. Among its recent "popular science" publications was The Meme Machine by Dr Susan Blackmore, a Zen practitioner and senior lecturer in Psychology at Bristol University, where she teaches on parapsychology and consciousness. Her view is that, although humans are exploratory creatures, able to exploit and create new niches, the majority of us are cultural imitators.
Musing on the memetics of modern sexual behaviour which seems to defy genetic imperatives (celibacy, birth control, adoption, and so on), she speculates about whether memetic optimists are programmed to have more children.
To be horridly rational about it, memetics is all pseudo-scientific palaver, an analogy stretched too far, a metaphor gone badly to seed - but it's catchy and fun, and it's certainly not going to go away. Despite memetic fundamentalism, the "meme" word is a very elegant piece of intellectual shorthand; a rich lexicographical, and metaphorical tool - especially in an age in which, as never before, ideas often "take on a life of their own".