This article explores the meanings and themes associated with the scholarly field of purity and impurity in the Babylonian Talmud, as condensed in two distinct phrases (which correspond with names of specific tractates in the mishnaic Order of Purities): "Nega'im and Oholot" (lesions and tents) and "Uqtsin" (stalks). We examine the occurrences of these two titles in rabbinic texts, the contexts in which they are invoked, and the practices and behaviors with which they are associated, and argue that these subfields of purity and impurity function in the Babylonian Talmud as metonymies for the rabbinic study-culture itself. We show that this specific curricular engagement functions as a manifestation of certain capabilities, accomplishments, and methods of learning, which the rabbis simultaneously valorize and problematize. We propose that the choice of purity and impurity as the halakhic theme through which the rabbis engage in this critical self-reflection is not incidental, and derives from the nature of this field as one that is "man-made," given more than any other area of legislation to scholastic manipulation. In the final section of this paper, we show that these Talmudic passages share a number of features with monastic criticism of the East Syrian school movement, and that these shared tropes point to the complexities and inner conflicts of the rapidly evolving intellectual culture of late ancient Mesopotamia.