In this chapter, I propose to present Talmudic law starting from one of its most glaring specificities: the structural and structuring use of general cases—and, among them, especially borderline cases—in the elaboration and discussion of legal rules. According to Leib Moscovitz, Talmudic law may be characterized as lying midway between, on the one hand, ancient law, which operates on a case-by-case basis, and, on the other hand, the abstraction that is typical to most legal systems today. Instead of defining and conceptualizing, Talmudic law often tells cases which, by virtue of their general and sometimes extreme or borderline characteristics, make it possible to interrogate broader and abstract issues. This may already be observed in the elementary texts of Talmudic law, namely the Mishna and the Gemara. The Mishna, compiled by Rabbi Yehuda Ha-Nasi in the third century, systematically expresses rules in terms of miqre (case) and din (specific rule). The Gemara (sixth century), which comments on the Mishna, often takes as its starting point the question heykhi dami (“what is this case like?”), questioning cases presented in the Mishna on the light of extreme or borderline variables. This approach not only clarifies the rules, but also the abstract principles and legal reasoning that structure them. In parallel, the Gemara currently asks the question may nafqa minnah (“what comes out of it?”) in order to analyze concrete legal implications of the abstract principles deducted. Between the questions heykhi dami and may nafqa minnah, this chapter seeks to present the sources, principles and methods of interpretation and reasoning of this often unknown legal heritage.