The "scholars" of his time were quite unable to appreciate this beginning of science, which actually led to the contention of this school, in the first century B.C., that the earth was of spherical shape. Tsou Yen himself was ridiculed as a dreamer; but very soon, when the idea of the reciprocal destruction of the elements was applied, perhaps by Tsou Yen himself, to politics, namely when, in connection with the astronomical calculations much cultivated by this school and through the identification of dynasties with the five elements, the attempt was made to explain and to calculate the duration and the supersession of dynasties, strong pressure began to be brought to bear against this school. For hundreds of years its books were distributed and read only in secret, and many of its members were executed as revolutionaries. Thus, this school, instead of becoming the nucleus of a school of natural science, was driven underground. The secret societies which started to arise clearly from the first century B.C. on, but which may have been in existence earlier, adopted the politico-scientific ideas of Tsou Yen's school. Such secret societies have existed in China down to the present time. They all contained a strong religious, but heterodox element which can often be traced back to influences from a foreign religion. In times of peace they were centres of a true, emotional religiosity. In times of stress, a "messianic" element tended to become prominent: the world is bad and degenerating; morality and a just social order have decayed, but the coming of a savior is close; the saviour will bring a new, fair order and destroy those who are wicked. Tsou Yen's philosophy seemed to allow them to calculate when this new order would start; later secret societies contained ideas from Iranian Mazdaism, Manichaeism and Buddhism, mixed with traits from the popular religions and often couched in terms taken from the Taoists. The members of such societies were, typically, ordinary farmers who here found an emotional outlet for their frustrations in daily life. In times of stress, members of the leading _élite_ often but not always established contacts with these societies, took over their leadership and led them to open rebellion. The fate of Tsou Yen's school did not mean that the Chinese did not develop in the field of sciences. At about Tsou Yen's lifetime, the first mathematical handbook was written. From these books it is obvious that the interest of the government in calculating the exact size of fields, the content of measures for grain, and other fiscal problems stimulated work in this field, just as astronomy developed from the interest of the government in the fixation of the calendar. Science kept on developing in other fields, too, but mainly as a hobby of scholars and in the shops of craftsmen, if it did not have importance for the administration and especially taxation and budget calculations. Chapter Five THE CH'IN DYNASTY (256-207 B.C.)