In his teaching, he refused to endorse the growing division between sūtra and kōan methods, believing the means are determined by the capacity of the student. He employed the term shōgyoku as a virtual equivalent to upāya.
Among many works, his Muchū-mondō shū (Dialogue in a Dream) explains Zen Buddhism in response to questions from the Shogun.
"Musō Soseki." The Concise Oxford Dictionary of World Religions. . Encyclopedia.com. (July 20, 2018). http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/muso-soseki
"Musō Soseki." The Concise Oxford Dictionary of World Religions. . Retrieved July 20, 2018 from Encyclopedia.com: http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/muso-soseki