According to Herbert Blumer, the most valid and desirable social research is conducted through qualitative, ethnographic methodology. He persistently critiqued the idea that the only form of valid knowledge is derived through a totally objective perspective. Blumer believed that theoretical and methodological approaches to studying human behavior must acknowledge human beings as thinking, acting, and interacting individuals and also must employ that represent the humanly known, socially created, and experienced world. As this directly challenges the thought process of traditional, positivism-based approach to sociological method, much controversy surrounds Blumer's sociological approach to empirical research.