Last year, in 2017, The Behaviormetric Society conducted a symposium entitled “Behaviormetrika and Dr.Chikio Hayashi—Celebrating his 100 years from his birthday—.” This essay was revised and enlarged edition of my lecture at that symposium. In this essay, I tried to describe and analyze why Dr.Hayashi's methods, including “Idea of Quantification” and “Quantification theories” were so widely accepted and highly evaluated in many fields of academic societies, and influenced many areas of human societies. On group of “Quantification Theories”, the author has opinions that “Quantification Theory Family Ⅳ and Family Ⅵ” are specially unique and superb, hence contribute to policy decisions and social life in many ways. So, the author discussed on these two models, introducing several interesting research examples. On the naming for “Quantification theories” by myself, Use and Up-use of naming were discussed, which made clear Dr.Hayashi's intentions of developing his theories and methods. Finally, the author picking up especially MDA-OR and MDA-UO by Dr.Hayashi, tried to discuss the unique and useful models of MDS, Multi-Dimensional-Scaling.
