Kang's best-known and probably most controversial work is
Datong Shu (大同書). The title of the book derives from the name of a society modeled on the period of "three dynasties" as imagined by Confucius, but it literally means "The Book of Great Unity". The ideas of this book appeared in his lecture notes from 1884. Encouraged by his students, he worked on this book for the next two decades, but it was not until his exile in
India that he finished the first draft. The first two chapters of the book were published in Japan in the 1900s, but the book was not published in its entirety until 1935, about seven years after his death. Kang drew a historical theory of world order which, projected into future, outlines world unification, and combined a future unified world with his utopian ideas. His historical theory points to a millennia-long trend towards ever-larger empires. {{blockquote Kang also made predictions about future trends towards world unification."The trend of imperial expansions will culminate with the contest between Germany and the United States." The author of a more famous
One World, the 1940 presidential candidate,
Wendell Willkie, similarly stated that either Berlin will be capital of the world, or Washington. Contrary to his Western contemporaries, commented Historian Max Ostrovsky, Kang belonged to a civilization which experienced millennia-long universal unity. He knew how it was unified and several times reunified. Naturally, his theory of the world unification is more sound than the abstract ideas of the “Federation of the world” by his Western contemporary colleagues. Kang divided history on three basic periods — prehistory, history till the moment of unification which is still to come, and future period of One World — and designed a table on several pages of features corresponding to each period. His later German colleague,
Karl Jaspers, independently designed three perfectly corresponding stages of history which he called prehistory, history and world or planetary history. The future unified world, in Kang's utopian design, would be democratically ruled by one central government. In his scheme, the world would be split into rectangular administrative districts, which would be self-governing under a direct democracy but loyal to a central world government. There would also be the dissolution of racial boundaries. Kang outlines an immensely ambitious, and equally inhumane,
eugenics program that would eliminate the "brown and black" racial phenotype after a millennium and lead to the emergence of a fair-skinned homogeneous human race whose members would "be the same color, the same appearance, the same size, and the same intelligence." Some of the methods envisioned for achieving this end included forced relocation to colder regions inhabited by whites coupled with sterilization of those suffering from diseases or whose mental and/or physical attributes were deemed exceptionally grotesque. One of the more humane tactics involved giving distinctive honors to white and yellow people who were willing to “improve humanity" by procreating with their brown and black counterparts. It is worth noting that although Kang felt that the white and yellow phenotype could coexist in his ideal scheme, he ultimately felt that white was nonetheless superior to yellow, and that the latter under ideal circumstances could be eliminated within the span of a century (prior to the advent of the "Great Unity"). Kang wrote that the traditional family structure should be abolished and that women and men should sign one year marriage contracts, thereby allowing for flexible and voluntary relationships. His desire to end the traditional Chinese family structure defines him as an early advocate of women's independence in China. He reasoned that the institution of the family practiced by society since the beginning of time was a great cause of strife. The family would be replaced by state-run institutions, such as womb-teaching institutions, nurseries and schools. Marriage would be replaced by one-year contracts between a woman and a man. Kang considered the contemporary form of marriage, in which a woman was trapped for a lifetime, to be too oppressive. Kang believed in equality between men and women and that there should be no social barrier barring women from doing whatever men can do. Kang saw
capitalism as an inherently evil system. He believed that government should establish
socialist institutions to overlook the welfare of each individual. At one point, he even advocated that government should adopt the methods of "
communism" although it is debated what Kang meant by this term. In this spirit, in addition to establishing government nurseries and schools to replace the institution of the family, he also envisioned government-run retirement homes for the elderly. It is debated whether Kang's socialist ideas were inspired more by Western thought or by traditional Confucian ideals. Laurence G. Thompsom believes that his socialism was based on traditional Chinese ideals. His work is permeated with the Confucian ideal of
ren (仁), or
humanity. However, Thompson also noted a reference by Kang to
Fourier. Thus, some Chinese scholars believe that Kang's socialist ideals were influenced by Western intellectuals after his exile in 1898. Notable in Kang's
Datong Shu were his enthusiasm for and his belief in bettering humanity through technology, unusual for a Confucian scholar during his time. He believed that Western technological progress had a central role in saving humanity. While many scholars of his time continued to maintain the belief that Western technology should be adopted only to defend China against the West, he seemed to whole-heartedly embrace the modern idea that technology is integral for advancing mankind. Before anything of modern scale had been built, he foresaw a global telegraphic and telephone network. He also believed that as a result of technological advances, each individual would only need to work three or four hours per day, a prediction that would be repeated by the most optimistic futurists later in the 20th century. When the book was first published, it was received with mixed reactions. Kang's support for the
Guangxu Emperor was seen as reactionary by many Chinese intellectuals, who believed that Kang's book was an elaborate joke and that he was merely acting as an apologist for the emperor as to how a utopian paradise could have developed if the Qing dynasty had been maintained. Others believe that Kang was a bold and daring protocommunist, who advocated modern Western socialism and communism. Amongst the latter was
Mao Zedong, who admired Kang Youwei and his socialist ideals in the
Datong Shu. Modern Chinese scholars now often take the view that Kang was an important advocate of Chinese socialism. Despite the controversy,
Datong Shu still remains popular. A Beijing publisher included it on the list of 100 most influential books in Chinese history. ==Philosophical views==