The methodology of Psak.

Abstract

Zot ha-Torah lo tehe muḥlefet;1 Halakhah is immutable. Therefore, Halakhah is not subject to change. Facts change; situations change. When applied to different facts and variegated situations, halakhic determinations need not be uniform but they are not inconsistent. Halakhah exists in two diverse realms: in the abstract and in the concrete. There is certainly room for disagreement and controversy in the realm of theoretical Halakhah – Elu va-elu divrei Elokim ḥayyim. But it is impossible to apply conflicting theoretical principles to matters of normative practice. Perforce, Halakhah must incorporate canons of decision-making. Those canons are themselves not without some degree of controversy. Thus, different decisors, applying different canons, may on occasion issue diverse rulings.