Saichō was one of the first Buddhist monks in Japan to argue that certain of his teachings were better suited to the period of the decline of Buddhism than those of his opponents. He did not, however, use the advent of mappō as the primary factor in justifying his reforms as did some monks in the late Heian and Kamakura periods. For example, Saichō never argued that the Fan wang precepts should replace the Ssu fen lü precepts precisely because it was the Period of the End of the Dharma (mappō).