Science Tribune - Article - July 1998
Memes, minds and selves
Department of Psychology, University of the West of England, Bristol BS16 2JP, UK.
Tackling the subject of memes
"Memes" (a). When you hear that word, or worse still find yourself saying it, do you get an irresistible urge to raise your hands in scare quotes or giggle nervously to hide your embarrassment? If so you are not alone. The very idea of the meme seems to strike fear into even the most hardened evolutionist.
Some reject the meme outright as a "meaningless metaphor" (1) (b) or empty analogy. However, my intention today is to argue that the idea of memes as independent replicators is a useful and powerful idea, and one that will prove essential to understanding the human mind.
I shall first outline the history of the idea of memes and then present four examples of how a theory of memetics can be used to explain specific phenomena; two of these I shall skip over quickly just to give an idea of the kind of reasoning involved. The others I shall consider in more detail. These are the origins of human altruism and the size of our brains. I shall conclude with some thoughts on the nature of minds and selves.
Dawkins, daring as ever
In 1976 Dawkins published his best-selling The selfish gene (2). This book popularised the growing view in biology that natural selection proceeds not in the interest of the species or of the group, nor even of the individual, but in the interest of the genes. The genes are the true replicators and it is their competition that drives the evolution of biological design or, as he would now put it, Climbing Mount Improbable (3).
It is often allowed to elderly and famous men that they can get away with a few pages of wild speculation on forbidden topics at the very end of their great books. I well remember my tutor warning me off the last chapter of Eccles' book on the physiology of the giant squid axon in which he tackled the naughty subject of consciousness. Well, Dawkins was neither old nor (then) terribly famous, but he devoted his last few pages to the topic of memes and has been much derided for it.
Dawkins, clear and daring as always, suggested that all life everywhere in the universe must evolve by the differential survival of slightly inaccurate self-replicating entities. Furthermore, these replicators automatically band together in groups to create systems, or machines, that carry them around and work to favour their continued replication (The selfish gene p 322) (2). The gene, he claimed, is not the only replicator on our planet. Staring us in the face, though still drifting clumsily about in its primeval soup of culture, is another replicator - a unit of imitation. He gave it the name "meme", and as examples suggested "tunes, ideas, catch-phrases, clothes fashions, ways of making pots or of building arches."(p 192) (2).
In just those few pages he laid the foundations for understanding the evolution of memes. He discussed their propagation by jumping from brain to brain, likened them to parasites infecting a host, treated them as living structures, and showed how mutually assisting memes will group together. He laid the basis for his later analysis of religions as co-adapted meme-complexes (4) and argued that once a new replicator arises it will tend to take over and begin a new kind of evolution. Above all he treated them as independent replicators, chastising those of his colleagues who tended always to go back to "biological advantage" to answer questions about human behaviour. Yes, he agreed, we got our brains for biological (genetic) reasons but now we have them a new replicator has been unleashed and it need not be subservient to the old.
Into the dictionary
The word has finally made it into the latest edition of the Oxford English Dictionary which defines meme as "a self-replicating element of culture passed on by imitation". However, the basic idea does not seem to have been either understood or much used and its two greatest proponents, Dawkins and Dennett, have both seemed to draw back from the idea after their initial enthusiasm (5).
Many writers prefer to avoid the term altogether. "Meme" does not even appear in the index of many of the best recent books about human origins and language such as Pinker's The language instinct (6), Dunbar's Grooming, gossip and the evolution of language (7), Mithen's Prehistory of the mind (8), or Tudge's The day before yesterday (9), nor in those about human morality such as Ridley's The origins of virtue (10), or Wright's The moral animal (11) (c).
There have been many attempts to develop theories of the origins of culture. Perhaps these use the same idea but call it something else. Such theories might roughly be seen as falling along a continuum from the outright rejection of cultural evolution (12), through most of sociobiology and Wilson's image of the genes holding culture on a leash (13), to schemes that treat cultural evolution as relatively independent. Among the latter, only Durham uses the word "meme" and it may be no coincidence that he provides good examples of the memes acting against the interest of the genes or forcing the development of the genes in one direction rather than another. However, even he makes inclusive fitness the final arbiter in his theory of coevolution (14). As far as I can understand them, other authors do not really treat their unit of cultural exchange as an independent replicator (15) (16) (17) (d). When it comes to the crunch they always fall back on appeals to biological advantage, just as Dawkins complained that his colleagues did twenty years ago.
Successful memes versus successful genes
Dawkins is clear on this issue when he says "there is no reason why success in a meme should have any connection whatever with genetic success". I agree.
The most direct support for this view comes from a philosopher, not a biologist. Dan Dennett has used the idea of memes in both his recent books (5) (18). He is absolutely clear that the meme is a separate replicator and describes its "replicator power" in terms of the fundamental algorithm of natural selection. He also goes further, describing a person as the entity created when "a particular sort of animal is properly furnished by - or infested with - memes" (Darwin's dangerous idea) (5) (p 341). His analysis is thorough and fascinating, but he does not make specific empirical predictions and few seem to have taken up his ideas.
There is a flourishing internet community communicating about memes, but as with all such groups the quality is mixed (e). Twenty years on, it therefore seems necessary for me to defend the very idea that the meme is a replicator in its own right, as well as to prove its usefulness.
The meme as replicator
It is widely agreed that for evolution to occur three things are needed; variation, heredity (or replication), and differential survival of the copies made. There is enormous variety in the behaviours human beings emit, these behaviours are copied, more or less accurately by other human beings, and not all the copies survive. The meme therefore fits perfectly.
Think of tunes, for example. Millions of variants are sung by millions of people. Only a few get passed on and repeated and even fewer make it into the pop charts or the collections of classics. Scientific papers proliferate but only a few get long listings in the citation indexes. Only a few of the disgusting concoctions made in woks actually make it onto the TV shows that tell you how to Wok things and only a few of my brilliant ideas have ever been appreciated by anyone! In other words, competition to get copied is fierce.
Put another way, there needs to be a replicator that makes slightly inaccurate copies of itself in an environment in which not all the copies can survive. Whichever way you look at it, the meme seems to fit. However, there are some cogent objections to the notion of the meme as replicator. I shall consider three.
Objection 1. Memes are not like genes
Unfortunately we only have one other well-known replicator with which to compare the meme. I say unfortunately because this tends to make us think that all replicators must be like genes. In fact genes may be just one example of many potential replicators (this is discussed in detail on p 110 of (19); see also p 200 of (18) and (f)).
So we need not reject the idea of the meme just because it works so differently from the gene. I suggest we should simply bear in mind the similarities and differences and wait to find out how important these are. In definition genes and memes are comparable. The gene is an instruction for building proteins, stored in a cell and passed on by reproduction. The meme is an instruction for producing behaviour, stored in a brain and passed on to other brains by imitation (g). However, there are many differences in the way the replication takes place.
Genes use the cellular machinery to copy themselves rather accurately. Memes have to be copied by using the brain itself as the replicating machinery. One person has to observe another's behaviour and work out somehow how to reproduce it. It is, if you like, a kind of reverse engineering. Say you snap your fingers above your head. I can copy this action relatively easily, yet the processes involved in my doing so must be fiendishly complex and we are nowhere near to understanding them. What we do know is that humans are supremely good at imitating each other and do so a great deal from very early on in their lives. It is this fiendishly complicated process that makes the transmission of memes possible.
Is memetic transmission Lamarckian?
This fact also means that memetic transmission is in some sense Lamarckian. That is, I copy the actions you make, not the instructions your brains holds for making those actions. But don't forget that we can easily ignore the vagaries of environmental constraints on behaviour. If I trip over when demonstrating my fantastic new combined garden hose and cat scarer, you will not copy my clumsiness when turning the invention on me. If I tell you a brilliant story when I have a sore throat, you will not assume a hoarse voice when passing on the gossip to your friends. Indeed language appears remarkably resistant to the vagaries of individual voices and accents and language must be a major way of passing on memes.
Whether we see the process as Lamarckian also depends in part on what we consider the equivalent of the phenotype to be. If we follow some authors in persisting in seeing the organism as the phenotype, then obviously the process is Lamarckian. If we follow Dawkins in treating meme products such as words, music, gestures, skills and fashions, as the equivalent of the phenotype, then the process still appears Lamarckian because these are the very things that are copied. However, we might follow his other suggestion that memes are still drifting clumsily about in their primeval soup (h). We can see the brain as the replicating machinery for behaviours which have not yet created clear phenotypes. In this case the process is not so obviously Lamarckian.
Accuracy of replication of memes
Does it matter that the copying of memes is so sloppy compared with meiosis? A topic for another lecture might be the way in which language, writing and reading, increase the accuracy of transmission and hence speed up the algorithm of memetic evolution. The creation of even more precise computer languages and software packages, not to mention hardware, may be another step in the same direction.
Speed of replication of memes
This relates to another important difference, often noted, that is the speed of replication. If there can be said to be a generation time for a meme, it can be as short as the time it takes to copy an action or a word or two. Most memes will hang around in various brains for weeks, months or years before being passed on, but many spread at fearsome rates. The news that Fergie spent a million pounds on a family holiday must have passed to millions of brains within a few hours of some journalist finding it out (or making it up).
I like to think of the question of speed in terms of Dennett's "tower of generate and test" taken from Darwin's dangerous idea (5) (pp 373-381). Darwinian creatures are generated by natural selection but have to die in the process. Skinnerian creatures can learn by trial and error and consequently can live on to repeat, or not, the behaviour they generate. Popperian creatures can imagine behaviours and decide whether to do them or not according to an internal generate and test. And finally, Gregorian creatures can pass on their clever tricks to others, so not every individual has to try the ideas out. Each floor of the tower builds on the last and each speeds up still further the process of accumulating clever tricks. Although Dennett does not explicitly say so, the fourth floor of the tower is the home of the memes - and they are generated, tested and accumulated faster than anything that has gone before.
Just how important these differences will prove to be, we shall have to wait and see. In the mean time I suggest we take careful note of them and use extreme care in transferring the use of terms such as genotype and phenotype, allele and generation to the world of memes. We may be able to use them or we may need to invent entirely new terms.
Objection 2. What is the unit of the meme?
This question is often asked and some people appear unwilling to proceed with memetics because the unit cannot be specified. However, we must remember that the same question can be asked of genes - indeed, Dawkins spells out in great detail the problems in choosing any particular size of unit (The selfish gene (2) p 28). Nature does not specify the size of a gene.
I also suggest that when I have explained my four suggestions, you ask yourself whether it matters what size of unit I am referring to. I have done this often myself and concluded that for many purposes we may proceed with a memetic analysis without specifying the size of the unit.
Objection 3. We do not know how memes work
No we do not - though we may speculate in terms of synaptic potentiation or variations in weights in neural networks. The fact is that when a person carries out any behaviour there must be some kind of instruction stored in the brain, and when someone else copies and remembers an action they must also create some kind of neural change. We can get a very long way without knowing how it is done - just as Darwinian theory got a very long way in the many decades before it was known that genes were the basis of heredity.
Overthrowing the objections and seeing what happens
I don't think any of these objections is worth worrying about. They are excuses not to try - and I want to try. I want to take the meme as a true replicator, selfishly copying itself in the world of human brains, and see what happens.
The basic approach I take is this - imagine a world full of hosts for memes (i.e. brains) and far more memes than can possibly finds homes. Now ask, which memes are more likely to find a safe home and get passed on again? It's that simple.
In the process I must assiduously avoid lapsing into considering either the interests of the genes or those of the organisms they create. I am concerned here with the selfish replication of memes and memes do not care either about genes or people. Nor do memes have foresight! I must also be careful of short-hand statements like "memes want x" "memes try to do y" or "z is a good meme strategy". These may be quite legitimate but I must always ensure that they can be translated back into the longer-winded version, such as "memes that have the effect of producing x are more likely to survive than those that do not." I have done this as well as I can and I hope you may enjoy thinking about some of the consequences of this way of thinking. Some of them are startlingly obvious - once you see them.
I will now outline four consequences. I shall treat the first two very briefly, partly as exercises in thinking memically.
Consequence 1. Why can't we stop thinking ?
Imagine a world full of brains, and far more memes than can possibly finds homes. Which memes are more likely to find a safe home and get passed on again?
Now imagine a meme that encourages its host to keep on mentally rehearsing it, or a tune that is so easy to hum that it goes round and round in your head, or a thought that just compels you to keep thinking it.
Imagine in contrast a meme that buries itself quietly in your memory and is never rehearsed, or a tune that is too unmemorable to go round in your head, or a thought that is too boring to think again.
Which will do better? Other things being equal, the first lot will. Rehearsal aids memory, and you are likely to express (or even sing) the ideas and tunes that fill your waking hours. What is the consequence? The memosphere fills up with catchy tunes, and thinkable thoughts and we all think an awful lot.
The principle here is familiar. In a forest any tree that grows tall gets more light. So genes for growing tall become more common and the forest ends up being as high as the trees can make it.
Consequence 2. Why do we talk so much?
We can apply the same principle again. Imagine a world full of brains, and far more memes than can possibly finds homes. Which memes are more likely to find a safe home and get passed on again?
Now imagine any meme that encourages talking. It might be an idea such as "talking is a great idea" or "it's friendly to chat". It might be some urgent thought that just compels you to speak it aloud. It might be just something terribly easy to say.
Imagine in contrast any meme that discourages talking, such as the thought "talking is a waste of time". It might be something you dare not voice aloud, or just something very difficult to say.
Which will do better? Put this way the answer is obvious. The first lot will be heard by more people and, other things being equal, simply must stand a better chance of being propagated. What is the consequence of this? The memosphere will fill up with memes that encourage talking and we will all talk an awful lot.
An alternative way of looking at it is this - people who talk more will, on average, spread more memes. So any memes which thrive in chatterboxes are likely to spread.
This makes me see conversation in a new light. Is all that talking really founded on the interests of the genes - on biological advantage? Talking takes a lot of energy and we do talk about some daft and pointless things! And what about thinking? Any meditator will tell you that the mind is constantly full of rubbish - thoughts that come and come and come and won't go away. Do these trivial and stupid thoughts have some hidden biological advantage? I would at least like to offer the suggestion that they do not. That we do all this talking and all this thinking merely because memes that make us do it are good survivors.
This sets the stage for a more audacious suggestion.
Consequence 3. Why are we so nice to each other?
Of course we aren't always nice to each other, but human co-operation and altruism are something of a mystery. Despite the tremendous advances made in understanding kin selection and inclusive fitness, reciprocal altruism and evolutionarily stable strategies, we do seem to do some peculiarly altruistic things (for good discussions see (10) (11) (20)).
Everyone can probably think up their own favourite example. Richard Dawkins (The selfish gene (2) p 230) calls blood doning "a genuine case of pure, disinterested altruism". I am more impressed by charitable giving to people in faraway countries who probably share as few of our genes as anyone on earth and whom we are unlikely ever to meet. Why do we hand in wallets found in the street, clear away rubbish on picnics, support eco-friendly companies or recycle our bottles? Why do so many people want to be poorly paid nurses and counsellors, social workers and psychotherapists? Many people believe all this must ultimately be explained in terms of biological advantage but I shall offer an alternative for consideration. We can use our, by now, familiar tactic.
Imagine a world full of brains, and far more memes than can possibly find homes. Which memes are more likely to find a safe home and get passed on again?
Imagine the sort of meme that encourages its host to be friendly and kind. They might be memes for throwing good parties, for being generous with the home-made marmalade, or being prepared to spend time listening to a friend's woes. Now compare this with memes for being unfriendly and mean - never giving dinners or buying drinks, and refusing to spare your time to listen. Which will spread more quickly?
The first type. People like to be with nice people. So those who harbour lots of friendliness memes will spend more time with others and have more chances to spread their memes. It is therefore in the interest of memes to get into nice people. In consequence many of us will end up harbouring lots of memes for being nice to others.
You may wish to challenge any of the above steps. It is therefore reassuring to learn from many experiments in social psychology, that people are more likely to adopt ideas from those they perceive as friendly or attractive. Whether this is a cause or a consequence of the above argument is debatable. It would be most interesting if psychological facts like this, or others such as cognitive dissonance, or the need for self esteem, could be derived from simple memetic principles - but that is a topic for another time!
For now we should consider whether the idea is testable. It predicts that people should act in ways that benefit the spread of their memes even at some cost to themselves. We are familiar with buying information and with buying a way into people's minds for the purposes of selling products, but this theory predicts that people will pay simply to spread the memes they hold - because the memes force them to. Many aspects of persuasion and conversion to causes may be turn out to involve this mechanism. Altruism may turn out to be yet another of the meme tricks that religions (those most powerful of meme-complexes) have purloined. Almost all of them thrive on making their members believe they are doing good.
Of course, being generous is expensive. There will always be pressure against it and if memes can find alternative strategies for spreading they will. For example, powerful people may be able to spread memes without being altruistic as well! However, that does not change the basic argument - that altruism is a good way to spread memes. If memes have replicator power we should expect them to press their carriers into service.
You may have noticed that the underlying theme in all of these arguments is that the memes may act in opposition to the interest of the genes. Thinking all the time may not be very expensive in energy terms - the brain is still using energy even when not thinking. However, it must cost something. Talking is certainly expensive, as anyone who has been seriously ill will attest. And of course any altruistic act is, by definition, costly to the actor.
I would say that this is just what we should expect if memes are truly independent replicators. They do not care either about the genes or about the creatures the genes have created. Their only interest is self-propagation. The consequence is that if they can propagate by stealing resources from the genes, they will do so. And of course this is not a recipe for human happiness.
I want to take just one more step along this path. My final example shows the memes forcing the hand of the genes in a much more physical way.
Consequence 4. Why are our brains so big?
Yes, I know this is an old chestnut, and there are lots and lots of good answers to the question. But are they good enough? Let us not forget how mysterious this issue really is. Brains are notoriously expensive both to build and to run. They take up about 2% of the body's weight but use about 20% of its energy. Our brains are three times the size of the brains of apes of equivalent body size. Compared to other mammals our encephalisation quotient is even higher, up to about 25 (21) (22). On many measures of brain capacity humans stand out alone. Brains are also dangerous organs to give birth to. The fact that such intelligence has arisen in an animal that stands upright may or may not be a coincidence but it certainly adds to the problem. Our pelvises are not ideally suited for giving birth to huge brains - yet we do it. Why?
The mystery was deepened for me by thinking about the size of the biological advantage required for survival. I was fascinated to read about a study addressing the question of the fate of the Neanderthals. Zubrow used computer simulations to determine the effect of a slight competitive edge and concluded that a 2% advantage could eliminate a competing population in less than a millennium (see Leakey (22) p 98 and Tudge (9)). If we only need such a tiny advantage why do we have such a large one?
Several new answers have recently been proposed. For example, Robin Dunbar (7) argues that we need large brains in order to gossip, and we need to gossip as a kind of verbal grooming to keep very large bands of people together. Christopher Wills (21) argues that the runaway evolution of the human brain results from an increasingly swift gene-environment feedback loop. Miller proposes that our vast brains have been created by sexual selection (for discussion see (23)); and Richerson and Boyd claim they are used for individual and social learning, favoured under increasing rates of environmental variation (17) p 75.
What these authors all have in common is that their ultimate appeal is to the genes. Like Dawkins' bewailed colleagues, they always wish to go back to biological advantage. I am going to propose an alternative based on memetic advantage.
Imagine early hominids who, for good biological reasons, gained the ability to imitate each other and to develop simple language. Once this step occurred memes could begin to spread. And also - once this step occurred the genes would no longer be able to stop the spread! Presumably the earliest memes would be useful ones, such as ways of making pots or knives, ways of catching or dismembering prey, and names for people, events and tools. Let us assume that some people would have slightly larger brains and that larger brains are better copiers. As more and more people began to pick up these early memes, the environment would change so that it became more and more necessary to have the skills in order to survive. So these slightly larger brained people would have an advantage. That, I propose, is how we got our big brains.
The process is related to the Baldwin Effect. I like to use Dennett's "tower of generate and test" again here.
On the ground floor are the Darwinian creatures. As these develop they change the environment in which they live, creating new selection pressures that lead to new design improvements. One result is larger brains capable of learning and the arrival of Skinnerian creatures. These again change their own environment, giving an advantage to the quicker learners. One aspect of quicker learning is internalisation - thinking before you act. So Popperian creatures are born and again change their environment so that better thinkers are at an advantage. Finally the ability to copy actions appears, giving rise to the Gregorian creatures and the birth of the new replicators - the memes. Creatures of this kind again change their environment so that those most able to adopt the memes are at an advantage.
Although the process is similar to all the previous ones, this last step is a big one. Note, most importantly, that it depends not on learning nor on cleverness per se but on the ability to imitate. A second replicator has now appeared that spreads at a fantastic rate and changes the environment as it goes.
An early hominid who was incapable of mastering any of the new techniques of tool making, speaking or hunting would be at some disadvantage, and the importance of this disadvantage would increase as the memes spread. In a population with few available memes, brain size would not be very important, in a population with lots of memes it would. It seems to me that this fundamental change in selection pressures, spreading at the rate of meme propagation, provides for the first time a plausible reason why our brains are totally out of line with all other brains on the planet. They have been même driven. One replicator has forced the moves of another.
Minds, memes and selves
We can now see the human mind as the creation of two replicators, one using the machinery created by the other for its replication. As Dennett pointed out, people are animals infested with memes. Our personalities, abilities and unique qualities derive from the complex interplay of these replicators. What then of our innermost selves - the "real me", the person who experiences "my" life?
I would say that selves are co-adapted meme complexes - though only one of many supported by any given brain. Like religions, political belief systems and cults, they are sets of memes that thrive in each other's company. Like religions, political belief systems and cults, they are safe havens for all sorts of travelling memes and they are protected from destruction by various meme-tricks. They do not have to be true.
In fact we know, of course, that selves are a myth. Look inside the brain and you find only neurons. You do not find the little person pulling the strings or the homunculus watching the show on an inner screen (i). You do not find the place where "my" conscious decisions are made. You do not find the thing that lovingly holds all those beliefs and opinions. Most of us still persist in thinking about ourselves that way. But the truth is - there is no one in there!
We now have a radically new answer to the question "Who am I?", and a rather terrifying one. "I" am one of the many co-adapted meme-complexes living within this brain. No wonder people want to raise their hands in scare quotes and giggle nervously at the very idea of "memes".
(a) This article is the text of a seminar given at The London School of Economics on Nov 28, 1996, as part of the series "About Biology". Science Tribune has published this text (with very minor editorial changes) with the kind permission of Dr. Susan Blackmore. It is also available on a Website devoted to memes http://www.memes.org.uk/meme-lab
(b) Gould used the term "meaningless metaphor" on Radio 4 Start the Week (Nov. 11, 1996).
(c) Nor is the word "meme" listed in the index of:
Barkow JH, Cosmides L, Tooby J. (eds) The adapted mind: Evolutionary psychology and the generation of culture. Oxford University Press, Oxford, 1992, nor of Wills C. The runaway brain: The evolution of human uniqueness. (21). On the other hand, Cronin H. The ant and the peacock(20) does have one entry.
(d) For example, Cavalli-Sforza and Feldman have developed a detailed scheme based on cultural traits, including notions of cultural fitness and cultural selection pressures, yet they seem to expect natural selection to rein in cultural evolution. Boyd and Richerson have analysed the forces of cultural adaptation and yet still, when they say "generation" they mean genetic generation, and when they say "adaptive" or "maladaptive" they mean for the genes.
(e) See for example
(f) Durham (14) (p 187) calls this principle "Campbell's Rule" quoting from Campbell (1965) "the analogy to cultural accumulations (is not) from organic evolution per se but rather from a general model for which organic evolution is but one instance."
(g) For definitions of the meme see Dawkins The selfish gene (2) p 192 and The extended phenotype (19) p 110.
(h) See Dawkins The selfish gene (2) p 192. R. Webb also takes this view. "Fossil soup: The evolution of technology: life as we know it or a pre-biotic soup? presented at LSE, 27 June 1996.
(i) Dennett (18) describes this imaginary place as the "Cartesian Theatre" and argues that we may reject Cartesian Dualism but still implicitly believe in the Cartesian Theatre.
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