This paper is based on two crucial assumptions. First, human-beings in general have a metaphorical way of thinking. The assumption has been clearly stated by Johnson when he defines metaphor as "a pervasive mode of understanding by which we project patterns from one domain of experience in order to structure another domain of a different kind. So conceived, metaphor is not merely a linguistic mode of expression; rather it is one of the chief cognitive structures by which we are able to have coherent, ordered experiences that we can reason about and make sense of. Through metaphor, we make use of patterns that obtain in our physical experience to organize our more abstract understanding." (Johnson 1987: xv) The second assumption, which may be called a weak Sapir Whorfian hypothesis, is that cultural and cognitive differences are, to some extent, reflected in the respective languages of human-beings. Of the first assumption, it will be shown that human beings in general focus on various features of a thing in building metaphorical expressions. To put it in more detail, the generation of metaphorical expressions is related to a way of thinking by which human-beings focus on some part or characteristic of a certain entity. This way of thinking may be said to be metonymical and synecdochical, or more generally metaphorical. Besides, it will be demonstrated that the characteristics of a concrete entity are projected in theory and argument building. Although Lakoff and Johnson (1980) has already clarified on this point citing examples in English, it will be shown that it is the case also in Japanese. Of the second assumption, it will be asserted that traditional characteristics of a thing and its users are reflected in metaphorical expressions. Consequently, it will be claimed that metaphorical expressions of each language inherit traditional and cultural aspects of an entity. This idea will be demonstrated by analyzing some expressions about houses and homes in English and Japanese. (Nobuaki Yamada)