In Isaac Newton's lifetime, no more than a few thousand people had any idea what he looked like, though he was one of England's most famous men, yet now millions of people have quite a clear idea—based on replicas of copies of rather poorly painted portraits. Even more pervasive and indelible are the smile of Mona Lisa, The Scream of Edvard Munch, and the silhouettes of various fiction extraterrestrials. These are memes, living a life of their own, independent of any physical reality. "This may not be what George Washington looked like then," a tour guide was overheard saying of the Gilbert Stuart painting at the Metropolitan Museum of Art, "but this is what he looks like now." Exactly.
For this bodiless replicator itself, Dawkins proposed a name. He called it the meme, and it became his most memorable invention, far more influential than his selfish genes or his later proselytizing against religiosity. "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," he wrote. They compete with one another for limited resources: brink time or bandwidth. They comet most of all for attention.
A stranger is at a party of people who know one another well. One says, "72," and everyone laughs. Another says,"29," and the party roars. The stranger asks what us going on. His neighbor said,"We have many jokes and we have told them so often that now we just use a number." The guest thought he'd try it, and after a few words said,"63." The response was feeble. "What's the matter, isn't this a joke?" "Oh, yes, that is one of our very best jokes, but you did not tell it well."