The Emperor Wu-tsang (r. 841-46) is now thought to have gone mad as a prelude to his persecution of the Buddhists. But his edicts were effective nonetheless. The state had begun tightening its grip on Buddhism when he came into power in 841, but in August 845 he issued the edict that ultimately had the effect of destroying traditional Buddhism and urbanized Northern Ch'an in China. Over a period of two years he destroyed 4,600 big temples and monasteries and over 40,000 smaller temples and retreats. He freed 150,000 male and female slaves or temple attendants and evicted some 265,000 monks and nuns, forcing them back into secular life. (This was out of a total Chinese population estimated to be around 27 million.) And not incidentally, the state reclaimed several million acres of property that had belonged to the monasteries. The effect of this was to obliterate virtually all the great Buddhist establishments, including the Buddhist strongholds in the capitals of Chang-an and Loyang, which were reduced to only two temples and thirty monks in each of the two cities.34 The irony of the Great Persecution was that it actually seemed to invigorate Southern Ch'an. For one thing, these rural Ch'an teachers had long been iconoclasts and outcasts themselves, as they disowned ostentatious temples and even the scriptures. Almost as much a philosophy as a religion, Southern Ch'an had long known how to do without imperial favor and largess. And when a further edict came down demanding that all Buddhist paraphernalia, including statues and paintings, be burned, the outcast Ch'an monasteries had the least to lose, since they had even done a bit of burning themselves--if we are to believe the story of Tan-hsia (738-824), a famous Ch'an monk who once burned a Buddhist statue for warmth. Southern Ch'an teachers just melted for a time back into secular life, from which they had never been far in any case.35 The result of all this was that after 846 the only sect of Buddhism with any strength at all was rural Ch'an. Chinese Buddhism literally became synonymous with Southern Ch'an--a far cry from the almost fugitive existence of the sect in earlier years. And when Buddhism became fashionable again during the Sung, Southern Ch'an became a house religion, as Northern had once been. The result was that Ch'an gradually lost its iconoclastic character. But out of this last phase of Ch'an developed one of the most powerful tools ever for enlightenment, the famous Zen koan, whose creation preserved something out of the dynamism of Ch'an's early centuries. PART III SECTARIANISM AND THE KOAN