12 Mark Washofsky

11. Analogy in Halakhah . Given that halakhah, traditional Jewish law, displays the characteristics of both law and ethics," it should not be surprising that analogy plays a major role in halakhic thinking. Any discussion of that role must distinguish between two major subject areas. The first of these concerns the extent to which the sages, the rabbis of the formative era of rabbinic Judaism , included analogy among their“hermeneutical principles”(midot she-hatorah nidreshet bahen), which served them in linking the content of the Oral Torah to the verses of the Written Torah. The various listings of these principles contain forms of comparison(hekesh, kal vachomer, binyav av) that can be termed“analogical,” although the precise characterization of each of them has long been a matter of controversy.* My concern here is not with these talmudic-midrashic midot but with the second large subject area: the use of analogy by rabbis in the Talmud and in the post-talmudic period as a means of learning the law in new cases by reasoning from already decided cases or rules. The term for this sort of analogical thinking is ledamoyei milta lemilta,“to compare one thing to another.” The ability to employ analogy to derive answers to new and difficult questions is considered central to the activity of halakhic scholarship and to the very conception of a rabbinical sage.'” At the same time, as we shall see, halakhic authorities express a distinct wariness over the process, out of concern that its unchecked or improper use can lead to mistaken conclusions. Rabbinical discussion of analogical reasoning tends to begin with a baraita in B. Bava Batra 130b: One should not derive the halakhah either from theoretical learning(limud**) or from a ruling in an actual case (maaseh) until one is instructed that“this halakhah is to be followed in an actual case(halakhah lemaaseh).” If one asks and is told“this is halakhah lemaaseh,” one may apply that ruling in an actual case, as long as one does not draw an analogy(between cases; uvilvad she-lo yedameh), The thrust of this text, as it is generally explained,” is that each of these methods of learning is afflicted with defects that can be corrected only when the two are combined. A student should not draw practical halakhic conclusions from his teacher’s theoretical discussion