spring books dimensions — the four dimensions of rela- zero) has always provoked the question of properties of replication, variation and tivistic space–time and six others of which whether spin is a property of particles or of competition is a “selfish replicator” that can we are unaware. Thus there is room for space. The materialization of particles from spread through populations by an analogue ample orthogonality to generate selection apparently empty space is similarly provok- of natural selection. qualify as repli- rules that prevent bizarre happenings ing. String theory neatly answers them all. cators because bits of culture can be copied between particles. So what lies ahead? Not even Greene is by imitation and compete with other units The most persuasive part of Greene’s sure. String theory may not turn out to be for human . Thus, despite the dif- excellent book is that in which he persuades the cat’s whiskers he hopes. There are alter- ferences between memes and genes (genes, the reader that the problem of the six hidden natives, such as ’s twistor the- for example, are almost never passed to dimensions is not a problem but a matter of ory (which Greene reckons may say the same unrelated individuals), those memes most perspective. A garden hose seen from a great as strings). The most imaginative suggestion easily replicated and mimicked could prolif- distance looks like a one-dimensional object, in this imaginative book is that the time has erate, causing swift and important cultural but close up it is plainly a two-dimensional come to solve problems of quantum gravity change. Alarmed by the rampant and surface on which motion perpendicular to in strictly quantum language and not by uncritical adoption of this analogy by the length is perforce circular and repetitive. posing them in classical terms and then philosophers, and the popular The length of the hose is Greene’s analogy for ‘quantizing’ them. Meanwhile, there is a press, Dawkins downplayed the importance an ordinary extended dimension; the per- whole raft of algebraic geometry to be done. of memes in his later works. pendicular circular tracks stand for one of The thousand and more people working in However, in his foreword to Susan Black- the six wrapped-up dimensions. If the radius the field will need courage to do these largely more’s The Machine, Dawkins notes of the circle (or of the garden hose) is small thankless chores, but this splendid book will that: “I was always open to the possibility enough, it is recognizable only in close-up cheer them on their way. that the meme might one day be developed (which means at the highest energy). Sir John Maddox is at 9 Pitt Street, into a proper hypothesis of the human How small are the compact radii? It W8 4NX, UK. , and I did not know how ambitious seems to be agreed that the compact dimen- such a thesis might turn out to be.” The sions must be curled up with a radius in the thesis, called “”, has now arrived, neighbourhood of the Planck length, which and it is indeed ambitious. Unfortunately, is the constant with the dimensions of The self-centred Blackmore’s book, aimed at both general length formed from Planck’s constant, New- readers and academics, proves to be a work ton’s gravitational constant and the velocity meme not of science, but of extreme advocacy. 3 of light. Formally, the length is Ꭷ(hG/c ), The Meme Machine Teeming with untestable speculations, where h and G are the quantum and gravita- by Susan Blackmore indifferent to alternative theories and tional constants and c is the velocity of : 1999. 258 pp. almost too grandiose to be taken seriously, light. Numerically, the length works out £18.99, $25 The Meme Machine offers a convoluted — ǁ35 at 10 m, which is small enough for Jerry A. Coyne and wholly unsatisfying — explanation of Greene’s purposes. cultural and biological . This is the kindergarten stuff of string The meme, defined as “any unit of cultural Blackmore defines memes as “units of theory, but Greene shrinks from no obstacle transmission or any unit of imitation”, was imitation”; her examples from humans in the path of understanding, instead turn- introduced by in the final include songs, fax machines, books, alcohol, ing each into an opportunity to make the chapter of . Dawkins’ mes- and any device, behaviour or idea that can be field exciting. The doctrine of supersymme- sage was that any entity with the gene-like copied. Memes can also be combined into

try has become an intrinsic part of string ON T theory — otherwise ‘superstring’ theory. W The implication is that there are as many VID NE fundamental particles yet to be discovered A D as are now known, but all of them are much more massive. String theory will fall if it is ever shown that they do not exist. The essential step forward, and the cause of Greene’s rekindled enthusiasm, was taken by Witten in 1995. He showed that the five alternative string theories then defined are essentially equivalent. A weak coupling con- stant (or the strings’ equivalent of electric charge) in one will be the equivalent of another theory with a strong coupling con- stant. So, says Greene, the road points ahead to the age-old dream of predicting both the contents of the Universe and the properties of those contents. Already there are people working on the notion that black holes are merely very massive elementary particles. Even if the dream proves false, Greene has brought an absorbing field of enquiry to vivid life. The supposition that particles are not points but strings fits well with familiar phenomena. The fact that all particles of matter have intrinsic spin (which may be

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“co-adapted meme complexes” that include support the sociobiological theory that some memes spread and not others — is a stimulus for imitation (“good girls don’t humans (especially females) are attracted by completely neglected. Why did Christianity have sex before marriage”), and into even power and its attendant resources. take hold during the waning days of the larger “”, such as religion, with Narrower hypotheses have additional Roman Empire? You won’t find the answer, many copy-able elements. Like Sherlock difficulties. A frequent problem is that the or any way to attain it, in memetics. (This, Holmes, Blackmore sees our as a room supposed meme seems to discourage its own by the way, makes memetics utterly unlike of limited size that can store only so many propagation. Such a case is Blackmore’s view biological evolution. The spread of genes memes. A meme’s success depends not on its that celibacy in Catholic priests is a meme through natural selection is not tautological benefits to the carrier, but on its ability to be that spreads by forcing clergy to divert their because one can predict their fate through replicated, retained and imitated. As she sexual energy into serving their religion. But their known effects on replication and the declares persistently: “If a meme can get what memes spring from this suppressed reproduction of their carriers.) itself successfully copied it will.” According sperm? If priests beseech their flocks to for- In a final effort to propagate her ideas, to Blackmore, this shibboleth explains ever refrain from reproduction, it is news to Blackmore constructs an extremely clever major aspects of our biology and culture, me. Other religions with non-celibate cler- coadapted meme complex: “Evolutionary including oversized , language, tech- ics, such as Islam, seem to have no trouble theory faced enormous opposition because nology, writing, contraception, adoption, attracting believers. it provided a view of humans that many altruism, vegetarianism, New Age ideas Finally, Blackmore sees as humans do not like. The same will probably such as alien abduction, and consciousness. a “selfplex”, an insidious band of memes that be true of memetics.” Well, call me Bishop Such an ambitious theory demands close conspire to give their carrier a false sense of Wilberforce, but in my view memetics is but scrutiny, but space restricts me to exploring self. Consciousness permits personal con- a flashy new wrapping around a parcel of old only a few of Blackmore’s views. She sug- viction, said to be especially good for and conventional ideas. gests, for example, that enlargement of the encouraging imitation (for example, “I love Jerry A. Coyne is in the Department of Ecology and human brain began when natural selection beer”). However, consciousness cannot be Evolution, The University of Chicago, 1101 East 57 improved the ability to imitate, followed by illusory: as the American philospher John Street, Chicago, Illinois 60637, USA. selection for ever more neurons to store suc- Searle has argued, thinking one is conscious cessful memes. Blackmore contends that is identical to being conscious. Moreover, such selection has occurred only in Blackmore’s scenario denies the possibility hominids and birds that learn songs. Subse- of consciousness to meme-less animals, and Shady secrets of the quently, memes further expanded our brain fails to explain the hardest problem of through sexual selection: as better imitators, human consciousness: subjective sensation. Enlightenment bigger-brained individuals are more attrac- How can memes account for the pain I feel Sex and the Gender Revolution, tive mates and leave more offspring. when I pinch myself? Volume 1: Heterosexuality and the One immediately smells trouble. First, But this is mere quibbling, for Black- Third Gender in Enlightenment there is no evidence that brain-size increase more’s enterprise has two fatal flaws. First, London had anything to do with memes — there are she has got the chain of causation back- by Randolph Trumbach as many explanations (including language, wards. The claim that memes created major University of Chicago Press: 1998. 484 pp. social grouping, hunting) as there are evolu- features of humanity is equivalent to the $35, £27.95 tionists, and no way to judge which theory is claim that the main force driving the devel- W. F. Bynum best. Indeed, the meme hypothesis seems opment of better computers has been the among the least likely. As others have noted, self-propagation of software. In reality, Sex and bodies have become fashionable the serious proliferation of memes began computers are usually designed for speed historical topics. Indeed, there are those who roughly 30,000 years ago when humans and capacity, which then permits the devel- believe that historians are a prurient lot, commenced their march to larger social opment of new software. Similarly, the self- preferring the bedroom to the laboratory, groups, writing and complex culture. The replication of memes does not mould our hospital, battlefield, palace and other sites human brain, however, stopped enlarging biology and culture; rather, our biology and where activities traditionally deemed more after reaching its present volume nearly culture determine which memes are created worthy of historical analysis take place. 500,000 years ago. Why did brain-size evo- and spread. What a world of human psy- Prurient or not, historians and social sci- lution stop so long before the heaviest rain of chology is obscured by Blackmore’s mantra, entists quite correctly insist that bedroom memes? “If a meme can get itself successfully copied behaviour can be exceptionally difficult to Although Blackmore deems memetics a it will”! To me, memetics boils down to the analyse. One of Randolph Trumbach’s adul- scientific idea, nearly all of her suggested following obvious theory: ideas tend to terers stuffed a handkerchief in the keyhole tests are either impossible to perform or spread if they cater to our desires to have of her bedroom door, so that her servants unable to rule out competing theories. For love, comfort, pleasure, power, sex, the could not spy on her. Even his randy men, example, she claims support for the sexual attention and admiration of others, a mean- who went with prostitutes in parks, ale- selection of memes, declaring that “... being ingful life and a way to evade the awful fact of houses or dark alleyways, were unlikely to highly articulate makes you sexually mortality. leave detailed accounts of their escapades. attractive. The history of love This brings us to the biggest prob- This, of course, makes eighteenth-century poems and love songs suggests lem: memetics seems complete- diarists such as James Boswell and William as much, as does the sexual ly tautological, unable to Byrd so attractive to historians, even if their behaviour of politicians, explain why a meme spreads class and status make them unsuitable for writers, and television stars.” except by asserting, post generalization about male behaviour down This may be true, but Black- facto, that it had qualities the ranks. more has forgotten sports enabling it to spread. One For the most part, then, Trumbach’s heroes, rock stars and super- might as well say that aspirin account of heterosexuality in eighteenth- models, also highly attractive relieves pain because of its century London relies on other kinds of but hardly known for elo- pain-relieving properties. The evidence, including newspapers, diaries, quence. The combined data better most interesting question — why correspondence and imaginative literature.

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