Meme

Overview
The word meme was coined in 1976 by scientist-author Richard Dawkins to describe the idea that ideas have discernable attributes that affect the ways in which those ideas spread.

Although it may seem that "idea" and "meme" are indistinguishable, since all ideas are memes and all memes are ideas, it is generally presumed that an "idea" spreads only if it is a good idea, i.e. an idea which is generally seen to be beneficial in some way. A successful "meme", however, may spread because of attributes which have nothing to do with the idea's inherent value.

For example: the idea that "Bill Gates is giving away one million dollars to the thousandth person who forwards the message you are currently reading to 10 of their friends" has spread repeatedly across the Internet – not because the idea is in any way valuable (since it is utterly false), but because it successfully masquerades (in a small but sufficient percentage of cases) as a valid idea and contains suggestions which further encourage its propagation (again, in a small but sufficient percentage of cases).

These percentages, though small, are sufficiently offset by the rate of spread that the idea has taken quite some time to die down, and still crops up from time to time as new hosts are exposed who have not yet been "immunized" by Snopes.com or a more knowledgeable friend.

It is the property of spreading in spite of being of questionable value (if not actually harmful) that is most notably "meme-ish" about some ideas.

Implications of Memetics

 * Not all ideas that are popular are actually good ideas. They may be harmful to the individual holding them, harmful to society, or both.
 * Just as diseases started spreading more rapidly through human populations when people began living closer together in cities, harmful memes spread more easily as we improve our information infrastructure and bring ourselves "closer together" in terms of communication, and we need to develop the tools to combat these harmful memes -- just as we developed modern medicine to counteract the spread of diseases.
 * This does not mean, however, that we need to censor or restrict communication anymore than the spread of disease in cities means we should stop having cities.
 * Some retroactive predictions
 * We should expect to see memetic viral "organisms" (MVOs) which successfully exploit flaws and idiosyncrasies in human nature to reproduce themselves. (Religion fits this description.)
 * We should expect to see a wide variety of the more successful variants of such organisms. (Religion also fits.)
 * We should expect to see some hostility and competition between the variants within the same region or "market". (Religion still fits.)
 * We should expect to see some traits in those MVOs which only make sense in the context of an earlier environment but are now vestigial (e.g. the Catholic assumption that anyone who would desecrate a Eucharist must be Jewish -- despite the fact that Eucharist desecration hasn't been used to stir up anti-Jewish sentiment for quite some time, and not with any regularity since the 1400s).

"Meme" vs. "Idea"
While a "meme" is really just an "idea" dressed in technical-sounding clothing, the point of using the word "meme" instead of "idea" is to help remove the tendency towards thinking of them along the same comfortable, well-worn tracks – in a sense, "de-anthropomorphizing" the basic concept of "an idea".

People typically take up ideas because they make sense, they accomplish something, they are in some way useful. Some ideas, however, don't make sense, or are even destructive, and yet seem to spread rapidly and remain tenaciously in place. The old response to this paradox was to sort of shrug and say "oh well, I guess people are just irrational sometimes". The "meme" concept, however, suggests a rational approach to understanding why and how such ideas spread.

Debate

 * Point: a "meme" is nothing more than an "idea". In other words, the theory has no explanatory force; it's just re-labeling.
 * Response: The re-labeling is nonetheless useful. Much as "aerodynamics" is really just "physics having to do with the interactions between quickly-moving gases and solid surfaces", "memetics" could be defined as "the ways in which ideas propagate and survive independently of their apparent accuracy, value, or usefulness".
 * Point: If (for example) someone could show something parallel to the forces that drive natural selection, that objection would be met.
 * Response: I believe I have at least indicated some directions for further investigation on this. I don't have time or resources to mount a full-fledged scientific investigation myself, but if you need something more specific I can probably come up with some testable hypotheses.
 * Point: Just us we see the force of natural selection when we see and measure the fact that faster antelope live longer and have more offspring, we need to see something measurable in the environment that allows successful memes to spread. As it is, all we know is that some spread and some do not.  There is rarely any clear reason.
 * Response: Here is a list of characteristics which help memes to be more successful. Environmental characteristics would only be necessary, I should think, in order to explain why some memes survive better in some environments and less well in others.
 * Point: And when there is [something measurable in the environement], such as in the case of the Copernican theory vs. the Ptolemaic, we can explain the success without recourse to memetics.
 * Response: This is an example of something which is clearly not "meme-ish", i.e. an idea which is innately valuable because it provides a more accurate understanding of the universe. The challenge answered by the "meme" concept is to explain the popularity of ideas whose innate value is questionable at best, and often negative – Scientology, chain mail, urban myths.

FAQ

 * Q: "...a rational approach to understanding why and how such ideas spread" – rational? How?  Unless the theory says why some memes spread better than others, it is circular, no?
 * A: The list of meme-ish traits would seem to be a good start on explaining how such ideas spread. Memetic theory is as yet in its infancy.
 * Q: OK, you are trying to provide a theory for the spread of ideas. Tough job!  But still, what does the neologism "meme" really add?  (The idea of spread and replication, I guess...but is that worthy of a new word?)
 * A: Do we really need a separate word for "aerodynamics" or "electronics" when they are both really just subsets of physics? When one speaks of "ideas", it is generally assumed that one is speaking of things with some level of innate value, and that it is the innate value which is interesting about them. When one speaks of "memes", it should be understood that one is speaking of things – ideas – that are interesting in spite of their lack of innate value.

Related Articles

 * Memes can spread through possession of inherent value or benefit, but they can also spread because of other more specifically meme-ish traits (i.e. experience memetic success).
 * Meme warfare is a struggle for dominance between mutually exclusive memes.
 * Power structure meme: a type of meme with a particular agenda

Quotes
The central question for meme theory is whether there are units of cultural imitation which behave as true replicators, like genes. I am not saying that memes necessarily are close analogues of genes, only that the more like genes they are, the better will meme theory work...