抄録
Recently, a term of "Security and Safety" has been widely used instead of a single term of "Safety" not only in mechanical fields but also in various fields in Japan. In the previous study, its fundamental concept is made clear by using a mathematical concept of "Projective Transformation". In this study, clarification of its fundamental concept is attempted by using concept of "Expression and Representation" which was submitted by G. W. Leibniz.
