This paper considers both how the mandatory introduction of student evaluation of teaching surveys (SETs) fits into the social and political context of tertiary education in Japan, and the assumptions about teaching underlying SETs. Through interviews with English teachers, a technical-rational perspective whereby teaching is a profession only to the extent that it involves applying theoretical knowledge to the pursuit of educational ends is discussed. Teachers' capacities to make complex judgments are not recognized so that teaching becomes indistinguishable from technical expertise. Quantitative evaluation as a measurement of effectiveness and efficiency leads to teacher exclusion from dialogue on how teaching might be improved.