meme(meem) n.
A unit of cultural information, such as a cultural practice or idea, that is transmitted verbally or by repeated action from one mind to another. Memes are the cultural counterpart of genes and can be considered the unit of cultural evolution. Ideas can evolve in a way analogous to biological evolution. Some ideas survive better than others; ideas can mutate through, for example, misunderstandings; and two ideas can recombine to produce a new idea involving elements of each parent idea.
Memes are contagious ideas, all competing for a share of our mind in a kind of Darwinian selection. As memes evolve, they become better and better at distracting and diverting our attention. They are viruses of the mind.
Individual slogans, catch-phrases, melodies, icons, inventions, and fashions are typical memes. An idea or information pattern is not a meme until it causes someone to replicate it, to repeat it to someone else. All transmitted knowledge is memetic.
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