The term "meme" was coined by Richard Dawkins (who contributes a Foreword to this book). It appeared almost as an afterthought at the end of his book "The Selfish Gene" in 1976, and he seems to have been taken slightly aback by the enthusiasm with which many readers took up the idea and ran with it. "Meme" has found a place in the Oxford Dictionary and there is now a "science of memetics". Memes are supposed to be analogous to genes; both are replicators, but while genes operate at the biological level, memes exist at the mental level in human beings and are units of imitation. Examples are such things as tunes, ideas, catch-phrases, styles, and fashions. (The very success of the meme idea is an instance of memetics at work.) Memes seek to survive and replicate themselves by passing from one human being to another, and they compete among themselves so that there are more successful and less successful memes.
Although the notion of a meme is intuitively appealing for many people, it is hard to pin it down and to make it rigorous. This is what Susan Blackmore has sought to do in her book. She starts by amplifying the concept and showing how it relates to Darwinian evolution. The important thing to grasp about this is that there is a general principle of replication at work here, which Blackmore calls universal Darwinism; although memes and genes don't function in exactly the same way, they, together with any other replicators there may be in the universe, must necessarily be subject to the process of natural selection which Darwin was the first to describe. Blackmore devotes four chapters to making this clear. She then goes on to tackle three difficulties with the memetic idea that have been raised by critics.
One problem is that it is hard to specify the unit of a meme, but, as she points out, the same is true of genes, yet this does not prevent the idea of a gene from being useful. There are important similarities but also important differences between memes and genes. A second problem is that we don't know the mechanism for copying and storing memes, but Blackmore doesn't think that this is a good reason for refusing to accept the idea. Finally, there is the question whether memetic evolution is "Lamarckian". Blackmore thinks that this question can only be asked meaningfully about biological evolution; it is misleading to apply it to other kinds of evolution such as that which characterizes memes. In summary, she thinks that memes are analogous to genes but we need not try to make the two equivalent at all points. Memes are important in their own right and do not depend upon genes for their validity.
With this preliminary stage-setting out of the way, Blackmore goes on to apply memetics to a number of aspects of human evolution and social questions, her claim being that the meme concept can offer explanations for various things which otherwise are difficult to account for. Her first topic is the human brain; why is it so large, and why do we have an intellectual capacity which is seemingly unnecessarily powerful for the lifestyle of our evolutionary ancestors? The answer, according to Blackmore, is that the evolution of large brains was driven by memetic, rather than genetic, selection, as early hominids began increasingly to imitate one another. The memes "needed" large brains and they created the environment within which the evolution of such brains would be favoured.
A related question concerns the origin of language, which is quite as contentious a matter as the evolution of the brain. Most attempts to construct a theory to explain how language arose are concerned with genetic selection, but Blackmore believes that it is better to think of Darwinian selection as operating on the memetic as well as the genetic level. "The human language faculty primarily provided a selective advantage to memes, not genes. The memes then changed the environment in which the genes were selected, and so forced them to build better and better meme-spreading apparatus. In other words, the function of language is to spread memes." Blackmore admits that this theory is speculative, but she thinks it could be tested, perhaps by setting up a group of simple robots capable of developing a "language".
Later chapters are concerned with memes in the modern world; Blackmore looks at how memetics can illuminate sociobiology, in relation to sex, altruism, "New Age" ideas, and religions. These large questions are, perhaps inevitably, treated rather less fully than some of the earlier topics. But Blackmore is not afraid to make clear where her own preferences lie: she holds that science is, in a sense, superior to religion, even though both are masses of memeplexes. Science does not offer us Ultimate Truth but it is a set of methods for trying to distinguish true memes from false ones. Religions, in contrast, are hostile to the testing of their theories about the world.
The final chapter puts forward what is probably the most contentious argument of all, for here Blackmore applies the meme idea to her view of the self. This recapitulates ideas she has already dealt with elsewhere (see the review of her book "Dying to Live", also on this site.) Her argument, which is influenced by Buddhist notions of "no self", is that the self is unreal, a construct, which she calls the "selfplex", by analogy with the term used for a collection of mutually cooperating memes, a "memeplex". By becoming aware of how the memes operate within our minds, she says, we can lessen our dependence on the selfplex and ultimately become free of its dominance. Although I think she may be right about this, it does raise the difficult question of how a mind which is made up of memes can ever become independent of the selfplex without ceasing to exist altogether.
The real question about the meme idea, it seems to me, is whether it is more than an appealing metaphor; is it a scientific theory? It may be too soon to decide this, but Blackmore certainly thinks it is scientific and she suggests a number of ways in which the theory makes testable predictions by which it will stand or fall. Her book is important because it treats the meme theory in depth. It is well written and will interest readers without a professional interest in the matter, but Blackmore has clearly kept at least one eye on the professionals and a full list of references is provided. She has set herself an ambitious balancing act in trying to cater for both classes of readers but I think she has largely succeeded. Anyone who is seriously interested in memetics is bound to read it, and for people who know nothing about the subject but want to find out, this is an excellent place to start.