Like the best detective novels, some academic works are impossible to put down before the denouement. Beyond the legal niceties typical of the genre, they deliver authentic sociological analyses of the “milieus” with which they deal. Time seems to stand still, the plot develops slowly, and the ending always comes as a surprise, with the previously confusing chain of events attaining a marvellous clarity.

Christine Mollier approaches Buddhism and Taoism in Medieval China by comparing literary works, rituals, and iconography. But here it is not a question of theft and murder but, at worst, of cases of plagiarism and piracy, and, at best, of adaptation. If, as the author points out in her introduction, Taoism's debt to Buddhism has long been recognised, the reverse process—Buddhism's borrowings from Taoism—has been neglected. To address this issue, Mollier examines three cases, three inquests in which Buddhism is very definitely in the frame: the meditative method of the Heavenly Kitchens, the ritual of Augmenting the Life Account, and the cult of the Great Dipper. In the interest of balance, she also examines the adaptation of the Buddhist divinity Guanyin in the guise of the Taoist god Heavenly Venerable Saviour from Sufferings. And, lastly, in the interest of neutrality, she provides an example of Buddhists and Taoists battling side by side against a common enemy: sorcerers. All the investigations are based on tangible facts, books, and icons; the most rigorous rules of history, philology and genealogy are applied, backed up by a detailed knowledge of the history of religions, with, as the principal scene, Dunhuang, where the most telling items of evidence are to be found.

In Chapter 1 (“The Heavenly Kitchens”), Mollier announces that although the oldest known manuscripts are Buddhist (7^th–8^th centuries), she is in no doubt that the Sutra of the Three Kitchens, Preached by the Buddha (Foshuo sanchu jing 佛說三廚經) was plagiarised from the Scripture of the Five Kitchens, Revealed by Laozi (Laozi shuo wuchu jing 老子說五廚經). This last, part of the Taoist Canon published at the end of the Ming Dynasty, includes a commentary by Yin Yin, the preface of which is dated 735; the Song anthology Yunji qijian lists two other versions, one of them attributed to Sima Chengzhen (647–735). Does this mean that the two versions are almost contemporary? Such a conclusion would not take into account the references to the “Kitchens” (referring to alimentary abstinence through meditative practices) evoked four centuries earlier by Ge Hong in the term “mobile Kitchens” (xing chu 行廚). In this context, Kitchens refer to a technique for visualising divinities in the cosmos and in the body of the adept and making possible miracles such as becoming invisible and summoning rain and thunder. While the practice of foregoing food in an attempt to achieve Nirvana is an integral part of Buddhism, it is clear that the Buddhist sutra is a maladroit reworking of a Taoist text, which “necessarily” predates it.

Following on from this case, Mollier extends her enquiry in Chapters 3 and 4 to two types of book: the first concentrating on the various ways of augmenting life capital (Yisuan jing 益算經), the other focusing on the cult of the Great Dipper (Beidou jing 北斗經), the aim of which was to obtain protection and lengthen one's life. Insofar as the different versions are concerned, we are practically in the same situation as the one which pertained to the preceding text: the oldest manuscripts in Dunhuang, dating from around the 7^th century, are thought to be Buddhist, and the Taoist examples—of which there are two, the first an almost perfect double of the supposedly Buddhist book, the second which seems to be a re-writing of it—are included in the Taoist Canon. Mollier again demonstrates that, whether from the point of view of the notion of a life account that can be lengthened or shortened according to our actions, of tutelary divinities (the six jia 六甲) or of litanies, it is clear that there must be a much earlier Taoist version which the “disciples of Buddha” pastiched by simply changing the terms tianzun 天尊 to Buddha and zhenren 真人 to bodhisattva and luohan, etc. The monk Yixing (683–727), a convert from Taoism to Tantric Buddhism, was effectively the first to include in one of his works details about the cult of the Great Dipper, attributing it unambiguously to a Taoist, Ge Xuan, the great uncle of Ge Hong. In reality, this cult may be a substitute for the meditative practices known as Pacing the Seven Stars (bu qixing gang 步七星綱) and Lying Down in the Dipper, which were very widely diffused amongst the adepts of the Shangqing current of Taoism in the period of the Six Dynasties.

In Chapter 5 (“Guanyin in a Taoist Guise”), the author deploys a contrary argument, examining the creation of a Taoist divinity, Jiuku yuanzun 救苦元尊, based on the great Buddhist figure, Guanyin 觀音. Mentioned in the writings of Lingbao around the 6^th–7^th centuries, Jiuku shares all the characteristics of Guanyin described in the Pumen pin 普門品 chapter of the Lotus Sutra, translated in China in the 3^rd century. Nevertheless, Mollier refuses to employ the terms “plagiarism” or “piracy” to characterise this transfer, preferring instead the words “adaptation” and “transposition,” acknowledging that the adepts of the Tao attempted to mark a difference with the original model, notably by making Jiuku a man rather than a woman, which Guanyin became under the Tang.

There is a point on which, instead of confronting one another, Buddhists and Taoists stand side by side: in the struggle against the sorcerers, or, more precisely, against bewitchments designed to cause harm (Chapter 2). It is certain that the Sutra for the Conjuration of Bewitchments, Preached by the Buddha (Foshuo zhoumei jing 佛說咒媚經) dates from the 6^th century. There are no less than thirteen copies of this sutra amongst the Dunhuang manuscripts. The stigmatization of sorcery is part of the Buddhist tradition: the Lotus Sutra mentions it as one of the afflictions characterizing the final years of the Dharma. Taoism has no particular interest in sorcery, but has tended to focus exclusively on demons, provoked not by sorcerers but by the bloody sacrifices made to them by shamans, both male and female. It was only in the Song Dynasty that Taoism, probably influenced by Tantrism and in concert with functionaries who tended to demonise the wu (“shamans”) in the non-Chinese ethnicities of southern China, was to take an interest in cases of bewitchment. The Scripture for Unbinding Curses, Revealed by the Most High Lord Lao (Taishang Laojun shuo jieshi zhouzu jing 太上老君說解釋咒詛經), published in the Tang Dynasty, is, from this point of view, an exception. Mollier places it in the context of the “Conversion of the Barbarians” (hua hu 化胡), as a response to the Buddhist sutra. The texts do reveal differences in the remedies adopted: whereas Buddhist circles seem to take recourse to an alliance between religion and medicine to ward off evil, the Taoists rely entirely on rituals and scriptures to deliver victims from bewitchments.

Christine Mollier's conclusion—the end of the inquest—is based on two hypotheses which may, at first sight, seem surprising. The first is a critique of the idea, defended in his time by Erik Zürcher, that only religious “specialists” were able to recognise the differences between religions and that simple believers were content to adhere to a confused and indistinct mass of popular religious practices. However, “specialists” were only able to produce “plagiarised” texts, “copies” and adaptations because the faithful, aligned in precisely defined socio-cultural classes, were perfectly well aware of the faith to which they belonged. Throughout the book's various chapters this theme is never directly addressed; instead, it is one of the logical and possible consequences of what is described therein. Nevertheless, the second hypothesis is the sum of the clues quietly distilled throughout the work and which a distracted reader may have missed: the existence of a third category of specialists made up of astrologers, diviners, and doctors, normally placed in the “amorphous” category of popular religion. If we re-read the book attentively, we are able to observe that, in the fields of the Celestial Kitchens, the augmentation of life capital, and the cult of the Great Dipper, they contribute by means of pharmacological manuals, apotropaic and mantic recipes, almanacs, and calendars, many of which are conserved in Dunhuang. Much more than that, since certain aspects of these techniques were attested to in the Han Dynasty, it is distinctly possible that, reinvested by the Taoists and the Buddhists, they returned, in around the 9^th–10^th centuries, to their original milieu: traditional Chinese religion. And neither are the practitioners of these techniques obscure figures; indeed, many of them were educated in the prefectural school of Dunhuang. It is evident that, contrary to what is suggested in the introduction, Christine Mollier's book cannot be reduced to a face-off between Taoists and Buddhists, to their “competitions for the religious” (Jean Levy), or to a defence and illustration of Taoism. Indeed, the book clearly demonstrates that there were often three players in the game.

Consequently, the way in which Buddhist sutras are presented as thefts, clones, and plagiarisms of Taoist books—when the Jiuku tianzun is a mere adaptation, a Taoist response to the great Buddhist divinity, Guanyin—is regrettable. Moreover, if a third party joined the dance of religions in medieval China, what is to be said of the category of “sorcerers” which seems to attract the ire of the specialists of the Tao and the Buddha? Is it destined, in turn, to become another amorphous religious category?