Inmo is a colloquial word in Chinese, and it means “it,” “that,” or “what.” We usually use the words “it,” “that,” or “what” to indicate something that we do not need to explain. Therefore Buddhist philosophers in China used the word inmo to suggest something ineffable. At the same time, one of the aims of studying Buddhism is to realize reality, and according to Buddhist philosophy, reality is something ineffable. So the word inmo was used to indicate the truth, or reality, which in Buddhist philosophy is originally ineffable. In this chapter Master Dogen explained the meaning of inmo, quoting the words of Master Ungo Doyo, Master Samghanandi, Master Daikan Eno, Master Sekito Kisen, and others.