Zeami adhered to a formalist writing process: he began with a topic, determined the structure, and finished by writing the lyrics. The number of plays that he wrote is uncertain, but numbers at least 30. His intellectual interests were eclectic and he was a proficient writer of Renga. "The Tale of the Heike" was the source of several of his best known plays. He integrated Japanese and Chinese ancient poetry into his drama. Contemporary dramatists Doami and Zoami had a significant influence on him, earning recognition in his treatises. He spoke particularly well of Zoami, but his shift toward Yugen and away from Monomane may have been because of Doami's influence. He mixed popular dance, drama, and music with classical poetics and thus broadened and popularized the classical tradition. In his earlier work, he used Zen illustrations, creating new Zen words and using established Zen words out of context. Many of the themes he used are present in other schools of Buddhism. Japan was dominated by a focus on Zen culture then, and he was registered at a Zen temple and was a friend of a well-known Zen priest. In 1422, he became a lay monk.