The paper deals with the sociologization of human sciences. Sociologization stands for sociological methodology and terminology application to humanities topics research. Many scholars leave their fields of expertise for sociological accounts of studied phenomenon. On top of that, social relationships account for phenomena and their development scrutinized within human studies. I enumerate fourfold argument for sociologization as an objective process in human sciences. First, sociologization impacted many different fields quite distant from each other, such as history and theory of translation. Second, a crossing of sociology with a particular branch of human science is marked by emergence of a new discipline related to sociology, such as historical sociology and sociology of translation sticking to the above-mentioned example. Third, there might be different sociologized disciplines within one field of expertise, such as historical sociology of literature, sociology of text and social semiotics to investigate literary texts, which are a prime object of my analysis in the paper. Fourth, sociology tends to replace philosophy to become a new metalanguage within human studies. I demonstrate efficiency of sociological approach using the example of attempted picturebooks definitins as a children literature genre or visual art. Efforts to define picturebook by applying classical methodology of literary and visual studies had been unsuccessful because of (1) the structural and content similarity of sequential literature genres and (2) continuing artistic experiments by picturebook authors. It turns out that picturebooks and comics might have much more in common than it was thought previously. Therefore, scholars were caught in a terminological impasse. The sociological methodology, namely ideas of sociology of text, yields a distinction of picturebook from comics in the description of different reading situations two genres anticipate. Although researchers, analyzed in the paper, do not portrait their approach as a sociological one, the applied methods and used terms refer to sociology of text.