In this paper, I examine the Postscript (batsubun 跋文) of the Yuishinshō-mon’i 唯信鈔文意 (T. 2658) and Ichinen-tanen-mon’i 一念多念文意 (T. 2657). In the postscript, Shinran refers to the students of Kanto who “do not know the heart of letters (文字のこころをしらない)” as “fools (愚者).” In previous studies, “fool” has basically been regarded negatively. In contrast, this paper redefines “fool” in a positive light as the ideal form of a nembutsu practitioner through a comparison with Hōnen’s Ichimai-kishō-mon 一枚起請文, which speaks of ichimon-fuchi no gudon no mi (一文不知の愚鈍の身).