UNTIL SIMON LEYS's book, Chinese Shadows , came along, the ancient and honorable diversion of describing one's travels in China had fallen upon hard times. With few exceptions, returning travelers had brought back only stereotyped reports of official briefings. Leys's book is a powerful antidote to such superficial reports. Eschewing the description of preselected factories and communes, Leys, an art historian with a penchant for politics, has written a fast-paced polemic about Maoist China, based upon six months' stay in 1972.

His perspective on the nature of Chinese Communist leadership will be particularly useful in the forthcoming reexamination of the Western role in China as a result of the recent triumph of centrists. If one agrees with Leys's conclusions that the current regime is deeply xenophobic and paranoid, Western hopes for a change in Chinese policy will be dashed.

Chinese Shadows is both more and less than a report on a trip. Since it is impossible to have sustained nonsanctioned contacts with Chinese people even when one speaks the language fluently, and since official contacts bring little more than tedious retelling of the party line. Leys could only view trivialities of everyday life, moods and movements, and attitudes observed hither and yon. However, he used these observations as a point of departure for a fruitful analysis of Chinese political reality and for reflection about the "style" of the Chinese regime, as well as the past history of the revolution.

The People's Republic is trying to fashion a new man and a new consciousness, Leys emphasines. This leads to an endemic contempt for history. His points out, for example, that no history of the Chinese Communist Party has been published. Thus, there is no need to rewrite to make it fit the exigencies of current policy.

In many other ways as well, the Chinese are being increasingly separated from their cultural heritage. During the Cultural Revolution, ancient statues were smashed by Red Guards, old temples were converted into warehouses, and museums were plundered. As late as 1972 and 1973, many museums remained closed; Leys surmises that their curators were being "reeducated" in the countryside, and the remaining collections remained in disarray. What the Cultural Revolution spared, the regime has often chosen to destroy. The walls surrounding the city of Peking and its impressive gates have been torn down. Tien Shan square, leading to the Imperial Palace, has been disfigured.

A Belgian art historian who specializes in China, Leys finds the architectural desecrations appalling. He reacts much like a frustrated lover, with violent feelings, and relates the destruction of the past to the nature of the political system.

China is unfailingly moving to an Orwellian 1964, he contends. The periodic purges are "the regime's safety valve . . . a periodic bloodletting that allows it to eliminate the toxins in its organism . . . The violence and the blood that always flows in these operations, the high positions and broad powers that once had been the preserve of the bureaucrats now found guilty - all this seems to show that a true revolution is occurring. In fact, the double cross is perfect, for the essence of the bureaucratic system is the interchangeability of bureaucrats, and no mere change of personnel could alter the nature of the regime."

Whether one agrees or disagrees with Leys, his strongly expressed views are worth pondering. They should not be dismissed out of hand just because he had minor lapses in not placing certain events in their correct historical context. For instance, he does not point out that the current style of Chinese invective, according to which a fallen leader may be accused of "apparently extreme leftist but in fact rightist" errors, actually derives from some of the less admirable features of Confucian or Buddhist traditions. But otherwise this book is a testimonial to how much can be observed by a trained Sinologist, conversant with the language and the history of the country, despite all the restrictions placed in his path.

The nonspecialist reader will enjoy Leys's retelling of the early ideological conflicts in Yennan, as he traces the origins of status consciousness in today's China. His thumbnail sketches, of contemporary political theorists and writers, and his reflections on Chinese history and culture, are equally successful.

In addition, the potential visitor to China can profit from some useful tips: how to gauge the status of various Chinese officials, for instance, (the important one have four pockets on their tunics) and how to determine whether it will be worthwhile talking to whatever guide is assigned by the authorities (Leys suggests one question which serves as a nearly infallible litmus test).

In Europe this book has won a prominent place in the new wave of publications which critically reexamine the conditions in Communist countries. Especially in France, where there is a high probability that a left wing coalition will win the next election, it has encouraged intellectuals to reassess the cost of "serving the people."

In the United States, Chinese Shadows should prompt a reevaluation of the purpose of our culture exchanges with China. Instead of encouraging unfocused forays to the mysterious East, we should insist that our contacts with Chinese scientists result in meaningful associations between people in similar disciplines. It is pointless to continue the current charade in which delegations of American professors who visit Chinese universities are not allowed to meet students in their own fields and are kept out of all classes except those that teach English. Simon Leys's book shows how silly such visits must appear to the Chinese.