… the hobgoblin of little minds.” (Ralph Waldo Emerson)
(daf 19b) The Mishnah brings to mind yet again that rabbinic reasoning is hermeneutical, not deductive. The sages work by analogy, association, exemplification, etc. Edward Hirsch Levi, of rabbinic forebears, wrote a terrific essay on U.S. law that – by analogy – reveals much of the accretive-processing of halakhah. An introduction to legal reasoning. (Levi was Attorney General and later President of the University of Chicago.) He lucidly explains legal developments in terms of “reasoning by example”, which is a charitable take on casuistry.
For law to be deductive, it presumably would be more faithful to the logical derivation of rules. Deduction sounds more universal, more consistent. Maimonidean.
Halakha is rife with qualifications, conditions, exceptions. For instance, one might expect the the sabbatical prohibition on work to apply at the very least to our most sacred activities and places. Yet the halakha makes a bold exception: on the Temple Mount itself, sacrifices on the Sabbath were carried out by the otherwise verboten acts of slaughtering and maintaining a fire.
The sages justify this bold exception with a midrashic interpretation of the rule to “not kindle a fire in all of your dwellings” (Exodus 35:3). The sages take “your dwellings” to include Jewish homes but to exclude ha-Shem’s House, i.e. the Temple.
By the way, this gives me a chance to plus one of my favorite books on midrash, halakha and language: Rabbinic Interpretation of Scripture in the Mishnah by Alexander Samely and his fan-tastic database of the Mishnahic exegesis and reasoning.