The Parasitic Meme
When Richard Dawkins introduced the word “meme” in The Selfish Gene he did so on the model of the word “gene”, and his discussion of the concept urged an analogy with genes—notably because both are replicators. I want to urge a different analogy (possibly identity), between memes and organisms: the meme is like (maybe is) a type of organism, specifically a parasite. Parasites are passed from host organism to host organism, seldom killing the host but syphoning off its energy resources. Typically they are hard to get rid off by normal mechanical means and can be a damn nuisance (sometimes worse). The parasite needs its host to survive, so too much debilitation is not desirable from its point of view: it must be relatively benign (not like a regular predator). Being a type of organism, usually small (fleas, lice, worms), it has both a phenotype and a genotype, these being geared to its life as a “guest at someone else’s table” (as the original Greek word suggests). It is also subject to random mutation and natural selection (sometimes intentional medical selection). It takes up residence in or on the body and proliferates from that snug perch. It is an animal like other animals, though a particularly crafty one. How then are memes significantly like parasites?
First we must overcome the idea that minds are non-biological things. I take it I don’t need to say much to dislodge that old idea: minds evolve, are aspects of brains, have a genetic basis, and are subject the usual rules of natural selection. Belief, desire, and consciousness are biological phenomena. Accordingly, memes, being mental entities, qualify as biological too—they are an aspect of the organism, a manifestation of life. But this is not sufficient to make them count as organisms themselves, even of the parasitic type. The question is whether they meet the other conditions for being (parasitic) organisms. They are clearly replicators, as organisms are, and also genes. Organisms replicate by generating offspring and not by simple division. Likewise, memes don’t divide into two when they replicate; rather, they generate copies of themselves in their hosts. So we know that memes are biological replicators, which is a good start. Further, we can say that they syphon off energy from their hosts: they take up residence in a human brain and persist there by dint of the energy available in a brain. No too much of that energy—that could be fatal—but enough to stay in existence and replicate themselves in another brain. Like parasites, memes can be a nuisance, but they are not usually so obtrusive as to threaten the life and health of the host. The lice in your hair may make your skin itch, and the memes in your mind can make your mind irritated—but they don’t kill you. You may want to get rid of an annoying jingle or manner of speech, as you may want to get rid of any parasites that come to your attention. Some parasites, however, are okay (gut bacteria) and some memes are welcome to stay. So we can say that memes have some of the causal, behavioral, and functional aspects of parasites: they operate in the same kind of way. They are not predators exactly, but they are scroungers, freeloaders, unwelcome guests (sometimes). Both have a sort of life of their own—a will of their own, interests of their own. The meme seems intent on its own survival even if you don’t like having it around: it is “selfish”. It is more organism-like than gene-like in this respect: more like an autonomous entity with self-directed goals. It is more like an active life form than a recipe for creating life forms.
But does the meme have a phenotype and a genotype? If we count language as a meme, a very large one, we can find literal equivalents of these notions: its phenotype is universal human grammar and its genotype is the genetic program that is innate in the human animal. Language genes build languages in brains, as limb genes build limbs in bodies. The language meme thus literally has a phenotype and genotype. But what about more standard examples of memes— such as jingles, fashions, and ideologies? Here the phenotype is the psychological profile of the meme: its phenomenology, semantic content, and behavioral dispositions. These determine (in conjunction with other factors) its staying power and contagiousness—its ability to survive and reproduce. A rapidly fading musical meme will not get transmitted, e.g. by humming. The meme’s phenotype is what seals its fate as a viable entity, particularly the way it meshes with the human mind. In this it is just like a parasitic organism. But does it have a genotype too? Possibly, if it is innately fixed, but generally not, so here the analogy may seem to break down. However, we must not be too parochial when it comes to genes. Not all life forms are necessarily grounded in DNA molecules; on other planets the underlying replicators might be chemically quite different. The abstract concept of the gene is just “whatever underlying structures account for heritability” or some such definition. Genes encode and they build—but they can do this in different ways in different conditions. So do memes harbor anything that meets this abstract description? I think they do and must. First, they are constructed from more primitive elements as they pass from one mind to another: it is not a matter of a rubber stamp or cookie-cutter. The meme can only enter another mind if it is first analyzed and then actively reproduced. The jingle must be heard and processed and converted into an inner melody: it must be capable of such analysis and conversion, and it must be constructed from simpler components (notes, rhythms, lyrics). The components have to be copied and strung together so as to resemble the original. This is a non-trivial task. Importantly, the brain must contain states and processes that correspond somehow to the meme’s apparent phenotype—hidden layers of machinery. This is starting to look a lot like a genetic substrate in the wide sense, i.e. a mechanism of transmission. Not chunks of DNA, to be sure, but units that act somewhat as DNA acts—constructively and reproductively. The meme has something analogous to cellular structure; indeed in the broad sense of “cell” (the word derives from monks’ cells) it has cells—basic compositional units. It has a fine-grained mechanism of reproduction that goes beyond its manifest phenotype. The efficiency of this mechanism is key to its survival and competitive potential—how well it does against other memes vying for the same mental space (“Jingle Wars”). So it looks like the analogy is holding up pretty well: memes are biological replicators with phenotypes and genotypes (widely conceived). Maybe they can even be said to grow and die: the Catholic meme grew over the centuries and it looks now to be in decline, possibly to die out eventually. Memes become extinct or lose their dominance (Beatle Mania, Communism, the Twist). They are parasites that have their day in the sun but can lose their grip with the passage of time, as bodily parasites can.
Memes are thus very like parasites, but are they literally parasites? It seems to me that this is not an unreasonable way to characterize them: once we get over the prejudice that minds are not biological the way is clear to classifying memes as mental parasites. They parasitize the mind (brain): they get in there and live off its resources. What if there were conscious physical parasites that invade the brain and suck up its nutrients, affecting the way the host’s mind functions? They might inject ideas into the host mind, possibly as an aid to their survival. Wouldn’t these be just like our memes—units of energy exploitation with a psychological nature? Parasites of the body have evolved in the usual way, and so have parasites of the mind—selfish replicators in their own right. Each has adopted the parasitic lifestyle, with the brain the focus of the mental kind. So there are actually two types of life on earth: the DNA-based type and the type preferred by the memes. We don’t know much about the basic processes and structures in the case of memes, but we have reason to believe that such processes and structures exist, maybe to be revealed by neuroscience. Perhaps there is a finite set of meme components for human memes and a finite number of combinatorial principles: these are the fundamental transmittable units of the meme universe. They may be quite ancient and fairly recondite—rather like genes—but they are the generative foundation of all meme activity. Whole ideologies may be the elephants of the memo-sphere, evolving from much smaller and simpler memes drawn from bygone days. If this is right, memes are literally living parasites feasting on the brain’s energy reserves.
 In fact Dawkins alludes to this possibility, quoting Nick Humphrey: “When you plant a fertile meme in my mind you literally parasitize my brain, turning it into a vehicle for the meme’s propagation in just the way that a virus may parasitize the genetic mechanism of a host cell” (p.192). However, he does not pursue this suggestion, preferring to focus on the analogy with genes. Whether other authors have run with the idea I don’t know.
 I remember an old Mike Leigh film in which a character went around the whole time singing, “Tasty, tasty, very very tasty; they’re very tasty”, clearly playing host to a meme he couldn’t control (even now that meme resonates in my mind).
 We have a name for this mechanism: imitation. But imitation is a complex process of analysis and synthesis, requiring underlying generative machinery, and capable of degrees of effectiveness. It is the meme analogue of the mechanism of inheritance that we now know is based on the DNA molecule (at least on planet earth).
 Parasites exploit weaknesses in the body’s defenses, immunological and mechanical; similarly memes exploit the mind’s natural receptivity and plasticity. It is good to be a fast learner, a cognitive sponge, but this can lead to stuff creeping in that does nobody any good. Dangerous ideologies are the price we pay for being easily educable—as parasites exploit the body’s surfeit of energy resources. The human mind is susceptible to meme intrusion because of its generous cognitive endowment; other animals are not much prone to such intrusion.