How much interpretation is too much?

THIS WEEK'S DAF YOMI COLUMN BY ADAM KIRSCH IN TABLET: Are Truffles Food? As our Talmud column returns, debates over Oral Law range from the existential to the mundane. Two topics from Tractate Eruvin in this one:

This numerical inflation reminded me of the saying chanted by the Israelites, in the First Book of Samuel, about Saul and David, comparing their greatness in battle: “Saul has slain his thousands, and David his tens of thousands.” In Talmudic times, Jewish manliness was no longer measured in Philistine corpses, but in legal creativity. Still, there is a point, Eruvin 13b teaches, beyond which a sage can become too intellectually advanced.

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What kinds of food, the rabbis ask, are capable of creating an eruv? Any food or drink, the Mishnah says in Eruvin 26b, except for salt and water. The food does not even have to be a kind that the person in question can actually eat. A Nazirite, for instance, vows not to drink wine, but it is permissible to use wine to create an eruv for him. This might seem so plain as to require no further discussion. But, of course, there is one, because of a principle the Gemara goes on to explain. “We cannot learn from general rules,” Rabbi Yochanan says, because any rule might carry unstated exceptions.

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