Meme replication

"The situation faced by memes is utterly different. Each meme has to be expressed as behaviour every time it is replicated. For it is that behaviour, and only that behaviour (given the environment created by all the other memes), that effects the replication. That is because a recipient cannot see the representation of the meme in the holder’s mind. A meme cannot be downloaded like a computer program. If it is not enacted, it will not be copied.

The upshot of this is that memes necessarily become embodied in two different physical forms alternately: as memories in a brain, and as behaviour."