Abstract: Japanese companies often criticize themselves on their own nurumayu [lukewarm] nature; however, in reality, according to Takahashi (1989), the lukewarm feeling felt by organization members can be explained through the effective temperature hypothesis. An organization's propensity to change as a system is measured as system temperature, while a member's propensity to change as an organization person is measured as body temperature. The lukewarm feeling felt by members can then be explained using effective temperature, which is defined as the system temperature minus the body temperature. This paper validates the effective temperature hypothesis using data from Survey X, an exhaustive survey of all employees of Japanese Company X, which is successful in organizational reform. The survey was carried out once a fiscal year, during the fiscal years 2004-2013. Like the results of the JPC Survey of Takahashi (2013), those of Survey X show the coefficient of determination of 0.9840 with a surprisingly neat straight line, demonstrating a direct relationship wherein the lukewarm feeling ratio drops as the effective temperature rises.Keywords: nurumayu, lukewarm feeling, thermometer, organizational climate, organizational culture, leading economic indicator1. IntroductionThe so-called nurumayu [lukewarm] nature of Japanese companies often tends to be viewed as a negative organizational climate or as a classic example of inactivated state of organizations. It is difficult to explain the nurumayu nature in English (Takahashi, 1992b). However, Takahashi (1989) successfully gives an explanation for it by testing the effective temperature hypothesis as a framework to explain the lukewarm feeling. The hypothesis is that effective temperature is defined as system temperature minus body temperature. Considered analogous to water temperature in a bathtub, system temperature means an organization's propensity to change1 as a system. In the same way, body temperature indicates the degree of member's propensity to change as an organization person.Question:Q1. Do you feel that the atmosphere at your work place is lukewarm (nurumayu)?Assuming that the lukewarm feeling ratio is the proportion of people who responded yes to the question (Q1), the effective temperature hypothesis can be expressed as follows.Effective Temperature HypothesisDefine the effective temperature (T) as follows:T = SINDEX - BINDEX.Then the lukewarm feeling ratio of a group is in reverse proportionto its mean of the effective temperature.The system temperature (SINDEX) and body temperature (BINDEX) here were measured as follows (Takahashi, 1997b), using the following questions.System Temperature:S1. Have high performing individuals been consistently promoted and given raises? ( 1 = yes; 0 = no)S2. Is avoiding failure considered more important than improving performance through trial and error? (1 = no; 0 = yes)S3. Is the atmosphere one which welcomes challenging new jobs? (1 = yes; 0 = no)S4. Is adopting the corporate culture more important than developing your own individuality? ( 1 = no; 0 = yes)S5. Is the atmosphere a competitive one in which members strive to achieve their goals? ( 1 = yes; 0 = no)Body Temperature:B1. Do you constantly seek improved ways of doing your jobs better than the others? ( 1 = yes; 0 = no)B2. Do you do your job in the way you want regardless of the way it was done in the past? ( 1 = yes; 0 = no)B3. Do you go out of your way to do new jobs before they are assigned to other departments? ( 1 = yes; 0 = no)B4. Do you believe you are able to cut your own way to success even in another company? ( 1 = yes; 0 = no)B5. Do you obey the orders of your superiors even if you disagree with them? ( 1 = no; 0 = yes)For these ten questions, the combined score for S1-S5 measured the system temperature (SINDEX), while that for B1-B5 measured the body temperature (BINDEX). …