An early Heian monk, founder of the Shingon school of esoteric Buddhism, known posthumously as Kōbō Daishi. Born in Sanuki, he traveled to Tang China in 804, received the esoteric transmission from the master Huiguo in Chang'an and returned in 806. He founded the monastery on Mount Kōya and made Tō-ji in Kyoto a center of Shingon practice. One of the three great calligraphers of his age, he wrote major doctrinal works and undertook public projects such as repairing the Mannō reservoir. Tradition credits him with the Iroha poem, though it was composed long after his death.
色は匂へど 散りぬるを
我が世誰ぞ 常ならむ
有為の奥山 今日越えて
浅き夢見じ 酔ひもせず
Colors are fragrant, yet they scatter and fall — / who in this world of ours could last forever? / Today I cross the deep mountains of being; / no more shallow dreams, no more drunken haze.