The distinction between “fact”and “opinion”has been seen as important, but it is difficult to distinguish them in the previous way. The traditional distinction between “fact”and “opinion”has generally been based on whether or not they are certain. However, we can not know the truth that something has actually happened and something is true for everyone. The definitions of “fact”and “opinion”differ from textbook to textbook. In the conventional distinction, the purpose of the writer / speaker’s statement has not been fully considered.
  In this paper, based on the concept of “direction of fit”in speech act theory, I define “sentences/utterances stated as fact”and “sentences/utterances stated as opinion”. The technical term direction of fit is used by speech act theory such as John Searle. “Sentences/utterances stated as fact”are defined as sentences/utterances stated by a writer/speaker for the purpose of fitting a word to the world (excluding fiction). “Sentences/utterances stated as opinion”are defined as sentences/utterances stated by a writer/speaker for the purpose of fitting the world to words (especially for the purpose of changing the other person’s beliefs). In the definition of this paper, it is possible to distinguish between “sentences/utterances stated as fact”and “sentences/utterances stated as opinion”regardless of the truth of whether something is really certain.

  This study focused on the science of picture books by Ichiro Sakamoto (1904-1987), a psychologist who specialized in language and reading, and highlighted the continuity in method and purpose between his exploration of story picture books and his exploration of popular children’s media, such as comic magazines and children’s magazines.
  Sakamoto has published many articles on cartoons and children’s magazines since the 1950s. He developed a quantitative analysis of a narrative that reinterpreted the findings of mythology, conducted a survey of children’s media use, and evaluated contemporary children's magazines. All of these were also applied to his exploration of story picture books sometime after 1970. Given the rapid proliferation of story picture books in the 1960s, Sakamoto considered it necessary to examine their value as one of the types of media to which children were exposed. However, this study also suggests that Sakamoto did not consider story picture books as disposable and inferior media, nor did he abandon the significance of picture books as a new form of literature for early childhood. This is because Sakamoto described contemporary Japanese story picture books as the product of certain improvements in quality resulting from the emulation of Western picture books. Previous studies have emphasized the rise of artistic criticism of picture books in the 1970s, but this study critically examined such an evaluation of the 1970s.