MODERN JAPANESE DIARIES: THE JAPANESE AT HOME AND ABROAD AS REVEALED THROUGH THEIR DIARIES By Donald Keene Henry Holt 534 pp., $50 When Japanese ventured abroad in the latter half of the 19th century, as their country reluctantly opened its doors to the gunboats of the United States, it must have seemed something akin to time travel. Agrarian Japan was, after all, a land where rice cultivation influenced daily rhythms, and respect for the samurai ethic ran deep. It was a country that for almost two centuries had cut itself off from trade and contact with most of the outside world. Beyond its isolated shores, however, lay a vastly different landscape. The West in many ways represented pure power: lands of seafaring traders, growing industrial might, and colonial tentacles that spanned the globe. It bombarded the Japanese consciousness with strange customs - women present in public gatherings, for example, and a shocking lack of propriety particularly noticeable in America. It gloried in its appreciation of modern science. It humiliated Japan's neighbor and teacher, China, by relentlessly carving the helpless giant into diplomatic ''spheres of influence.'' Donald Keene's collection of Japanese diaries sweeps the reader through the fascinating account of how a group of Japanese sized up Europe and America from the mid-19th century to the early part of the 20th. It vividly portrays the human face of a nation that, in just five decades, would transform itself from a curiosity to a power strong enough to defeat Russia in 1905. A relatively elite group of Japanese, from official emissaries to novelists, poets, and teachers, were witness to the extraordinary engagement between these two worlds through their travels to Europe and America, as well as colonized China and Southeast Asia. A few couldn't get back to Japan quickly enough. Others were dazzled by the West and wanted Japan to absorb its teachings rapidly. All, however, had something to say about this startling new world, and they chose to record their views in diaries. Keene, one of the foremost Western scholars of Japanese literature, has assembled a wide variety of their tomes. Through Keene's personable guidance, as well as his elegant translations, it is possible to glimpse the feelings of the Japanese as their country emerged on the global scene and scrambled to assimilate Western learning. Some were bound by duty, as officials of the shogun or, later, officials of the new Meiji government. Others were in search of knowledge to bring back to Japan, and some simply for adventure. One of the first arrivals on US shores, Muragaki Norimasa, a member of the first embassy sent in 1860, clearly understood the position in history his journey in the service of the shogun would take. ''I felt terrible pangs in my heart at the thought that someone as incapable as myself had been commanded to accompany the first Japanese mission ... since the creation of heaven and earth; if I should fail my lord ... what a disgrace it would be to the Land of the Gods!'' Muragaki was sure the West would look with respect upon Akishima, as he poetically referred to Japan. As time went on, though, several Japanese recognized that the competition was on Western terms, not Japanese. Reflecting on the death of a famous countryman at the turn of the century, writer Nagai Kafu lamented the end of a simpler era and the passing of a man ''unable to survive the struggle for existence of twentieth-century society.'' While many of the diary entries bear witness to Japan's tumultuous emergence from isolation, others deal with more mundane facets of leaving the islands. Food was a major concern, and the thought of being deprived of salted fish, rice, and seaweed sent a tremor through more than one Japanese traveler. Some of the assessments of international cuisine sounded at times like college students writing home about dining hall cuisine, saying that local fish tasted like mud, and decrying rice served with butter. Presaging future comments by other Japanese, Kimura Yoshitake, who commanded the first Japanese ship to travel with official permission since the early 1600s, summed up culinary matters succinctly: ''Food and customs are in general the same everywhere in the world. Only our country is different.'' The rapid introduction of Western life threw more serious challenges across the paths of late-19th-century Japanese. All struggled with the language barriers, and many were surprised and disheartened by pressures to convert to Christianity. In other ways, however, they admired the West and wanted Japan to be able to stand with it shoulder to shoulder, instead of as a subordinate. Japan's determination to achieve this might be seen in the number of observers who spoke respectfully of the British colonization efforts. Writer Mori Ogai, who spent several enthusiastic years in Germany, asked in a poem about Hong Kong, ''Who could have predicted this overgrown, uninhabited spot/ Ceded to the British would one day harbor countless ships?'' Indeed, in perhaps a harbinger of the future, many who traveled in Asia spoke with little respect for the societies they found there. Regardless of mourning the passing of an epoch, regardless of concern that Japan might lose its traditions in the onslaught of Western ideas, the need to meet the West on Western terms was deeply felt. Natsume Soseki - one of Japan's most famous writers, and one who had criticized almost everything he saw in his European travels - made this point in his diary, saying in 1901: ''It's all over with Japan unless it really opens its eyes.''