Christine Hayes puts the kibosh on the notion that there is a recognition of natural law in “Judaism.” She is, of course, careful to draw her analysis closely around a circumscribed group of sources. While arguably most medieval and a few contemporary Jewish philosophers recognize natural law as a basis for revealed law, the same cannot be said of the rabbis. This philosophical revelation about the history of Jewish thought appears in her recent What’s Divine About Divine Law? Early Perspectives.

Relying on Cicero, for Hayes what counts as natural law is set at a high bar. It might be argued against her that the bar has been set, indeed, too high. As distinct from conventional (positive) law, natural law is defined by Cicero as follows. “[T]rue law is right reason in agreement with nature; it is of universal application, unchanging, and everlasting…We cannot be freed from its obligations by senate or people, and we need not look outside ourselves for an expounder or interpreter of it. And there will not be different laws at Rome and at Athens, or different laws now and in the future, but one eternal and unchangeable law will be valid for all nations and all times” (Republic 22.211). As per Hayes, natural law is invariable, universal, and embedded in nature (p.355). To that one might add: immediately intuited. Presupposing a system without significant gaps between its various component parts, the definition assumes a basic and necessary harmony established between the human person in community with the order of nature writ large.

Regarding the rabbis, one of the more important prooftexts typically adduced to support the claim that they recognize natural law is from Sifra, the tannaitic commentary to Leviticus. That text reads, “‘You shall observe my judgements (mishpatim)’ –these are matters in the Torah which –had they not been written—it would be logical (=din) to write, such as robbery, sexual violations, idolatry, blasphemy, and bloodshed. If they had not been written it would be logical (=din) to write them. And those (i.e. ḥukkim) are the ones that the evil impulse and the idolatrous nations of the world object to, such as the prohibition against eating pork and against mixed seeds, and [ḥalitza], the purification for scale disease, the scapegoat ritual. The evil impulse and the idolatrous nations of the world object to them. Scripture says, ‘I am Yahweh’ meaning, you are not permitted to object to my statutes (ḥuqqotai)” (Sifra Aḥarei Mot 9:3) (Hayes, p.250).

Articulated first by Saadya Gaon, the distinction in medieval philosophy between rational commandments (mishpatim, usually translated into English as ordinances) and non-rational or even irrational ones (ḥuqqim, usually translated as statutes) have their rabbinic source here. Against the assumption made by contemporary natural law theorists, Hayes makes the counterintuitive case that the mishpatim do not meet the standard of natural law. As understood by her, reading the rabbinic source in context shows that at stake is God’s exclusive sovereignty over Israel, that Jews are not supposed to follow gentile customs, even if they are more attractive, and that much of God’s law does not agree with human nature. The very laws that would seem to be rational turn out, according to the rabbis, to be matters of divine fiat or decree (pp.248-60).

As for the so-called seven laws said to have been revealed by God to Noah and which are supposed to bind the nations of the world, Hayes argues that this is not “natural law.” In an early source such as Tosefta Avodah Zarah 8(9):4-9, these laws are not held up as invariable or universal. They are revealed by God, not by reason. And according to the early sources, Jews are not bound by the Noahide law (e.g. with respect to murder or robbery) in their relation with idolaters. Jews and non-Jews are enjoined to obey different prohibitions; in those cases that Jews and non-Jews fall under the same law, they suffer different punishments for violating the self-same law; after revelation at Sinai, Jews are not commanded to observe these ordinances. Hayes concludes that instead of constituting a common and basic form of shared natural law, the Noahide laws are instead “utilized precisely to inscribe rather than erase differences between Jew and non-Jew” (p.359-61).

The same is said to hold true for the discussion of the Noahide laws in the Babylonian Talmud (especially tractate Sanhedrin 56a-60a). In the famous story in which gentile nations refuse God’s Torah, they do so because they are addicted to basic prohibited acts like adultery, robbery, and murder. Again, the story’s point is that Jews and gentiles do not share a common human or natural moral constitution; those very laws that would seem to provide fundamental controls to human social life are seen as conventional positive law, not natural law (pp.366-8). As formulated in the rabbinic sources, even the Noahide laws have nothing to do with nature.

Hayes argument is not to address the coherence or incoherence of natural law as a theory. It is only to say that the theory has nothing to do with the rabbinic sources and “the Judaism” represented therein. Against Hayes, one could very well argue in the interest of a modified theory of natural law that what we mean by “nature” and “human nature” is nothing like what they were presumed to have been by Cicero. But what interests us is just how “unnatural” divine law or Torah turns out to be as presented by Hayes. No doubt, we’re un-romantic, more skeptical about nature as a value; and more modern and postmodern in our regard for artificial environments. Independent of the rabbis, what remains to be argued is a theory that splits the difference, that takes into account the blending in together of artificial and natural environments.