This article originally appeared in the Jewish Free Press, Calgary

Stincus, Scincus Shmincus--But Is It Kosher? *

All in all, it would appear that questions about the kosher status of fish should be among the least problematic areas of the Jewish dietary laws. The Torah offers very clear rules for identifying the permissible sea creatures: "whatever in the water has fins and scales." The Mishnah simplifies the process even more by observing that, while some species might have fins but no scales, all those with scales also have fins. This assumption allows for leniency in cases where the fins are not visible, either because they are too small or because they were removed before the Jewish consumer had a chance to examine the creature.

The halakhic waters got muddied, as it were, one day in the seventeenth century while Rabbi Yom Tov Lipmann Heller was occupying a rabbinical post in Vienna. A Jewish physician named Aaron Lucerna approached him bearing a creature with the charming name "stincus marinus" that inhabited the "Spanish Sea" (the southwest Mediterranean). Like the Japanese fugu puffer-fish, the stincus was said to be lethally poisonous until its toxin was removed by qualified experts, after which the leftovers could be utilized for assorted pharmaceutical purposes.

The main reason Dr. Lucerna thought the creature would be of interest to Rabbi Heller was because it had scales but no fins, thereby presenting an ostensible contradiction to the Mishnah's rule. How would the rabbi account for this contradiction between science and religious teachings?

An easy solution suggested by the doctor was that the stincus marinus did in fact have "fins" if one were allowed to employ a broad enough definition. For it had four little legs to propel itself, and perhaps those could be counted as fins for purposes of the halakhic classification.

However, Dr. Lucerna had another problem with the stincus marinus. Even if it technically passed the scales-and-fins test, there was something theologically disturbing about declaring it kosher. The fact that it was poisonous and, if improperly prepared, could kill a person who ingested it, seemed incongruous with the overriding spirit of Judaism. In this connection he quoted passages from the Talmud in which the rabbis insisted that all the precepts of the Torah were subject to the condition "her ways are pleasant ways, and all her paths are peace." Now the doctor argued, that principle should also preclude consuming an unpleasantly poisonous sea creature. How, then, could the stincus marinus  be permissible according to the Torah's values?

Rabbi Heller related that he was initially disconcerted by Dr. Lucerna's query and he was unable to come up with a satisfying retort. He suggested feebly that perhaps the Torah did not have this particular species in mind because it was not yet in existence in the days of Moses or of the talmudic rabbis, but was genetically engineered at a later date through cross-breeding. Even though he was able to adduce some midrashic statements about changes that had occurred in nature since the original creation, he was clearly not comfortable with that unlikely explanation.

Eventually the rabbi was able to come up with a more satisfactory solution, one that was rooted in the biblical text rather than in dubious scientific conjectures. His careful reading of the relevant scriptural passages led him to the conclusion that the Torah distinguished between fish and other aquatic creatures, and that the generalization about all scaled species having fins was only true with reference to fish. The stincus marinus, on the other hand, as a non-fish water animal, might well have scales and not fins.

We now know that the whole dilemma was based on a case of mistaken identity. The animal in question was mislabeled. Its real name was "scincus marinus" and it was a member of the skink family. As Rabbi Moses Schreiber (the "Hassam Sofer") would later report in the name of up-to-date scientific evidence, it was not a water-dweller at all, but a landlubber. In English too it is known misleadingly as a "sandfish," a name that it likely acquired by virtue of its remarkable talent for propelling itself under the sands by means of swimming-like strokes. These facts were unknown to the earlier Jewish scholars who participated in an animated debate that persisted for centuries. At any rate, what provoked this discussion was not the actual biological organism so much as the intriguing hypothetical concept of a poisonous, scaled and finless organism.  

Rabbi Heller's discussion was revisited a generation or so later by Rabbi Hezekiah da Silva, a scholar known for his contentious mindset. He was veritably fuming with righteous indignation at both of Heller's explanations of the stincus marinus: "Lord help him for publishing such foreign notions that all but uproot the boundaries and limits that were established by the ancients, thereby creating opportunities for people to succumb to errors and doubts with regard to the holy and true words of our blessed sages." 

Da Silva was convinced that if we were to concede the possibility that new species had come into existence since the days of the Bible and Talmud, then the eternal laws of Judaism would completely lose their validity. It was therefore preferable to suppose that Heller's stincus did originally have fins, but they had somehow dropped off before it was caught, or they had not yet reached their full maturity. Whatever biological objections might be implied in such a theory (and some later rabbis were quick to point these out), "it behooves us to seek after arguments that uphold the words of our revered sages rather than proposing theories that cast doubts on the rabbis' received traditions."

In a similar vein, Rabbi da Silva objected to Heller's hypothesis that the presence of scales without fins was not a sufficient criterion for permitting consumption of aquatic creatures other than fish. He therefore declared the stincus marinus to be kosher. As for the argument that the Torah would never allow us to eat a species that is potentially deadly, that factor was surely offset here by its pharmaceutical benefits. He noted that there are many medicinal products that are permitted by the Torah in spite of their potentially hazardous side-effects. His pious confidence in divine providence reassured him that the no innocent people would ever come to harm from ingesting stincus, as stated in Proverbs: "no harm befalls the righteous, but the wicked have their fill of trouble." (It seems to me that it would still be prudent to read the fine print on the label.)

The disagreement between Heller and da Silva defined the frame of reference for much subsequent discussion of these issues: Does piety demand a belief that the rabbis of yore possessed infallible expertise in ichthyology, knowledge that originated in divine inspiration rather than in academic scientific study? And do the Jewish dietary laws take into account health factors, or other moral and aesthetic considerations?

Some scholars, like Rabbis Jonathan Eybeschutz and Jacob Zvi Mecklenburg, resolved the problem quite simply by noting that it is virtually impossible to speak of invariable laws among the infinite varieties of biological phenomena; whereas the Torah concerns itself only with the most common situations. The Talmud itself declares that its generalizations are subject to exceptions. As Eybeschutz put it, "if you should discover a creature without fins, this does not disprove the general rule, because it is an exception, and the talmudic sages were speaking about the majority of fish."

I may be wrong, but I find something quintessentially Jewish in the way that this skirmish between science and religion came to focus not on broad cosmic questions like Evolution or the Big Bang, but on an unpretentiously practical problem about a seafood option on the dinner menu.

This article and many others are now included in the book

On the Trails of Tradition
On the Trails of Tradition

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  • First Publication:
    • The Jewish Free Press, Calgary, October 15, 2010, p. 10.
  • For further reading:
    • Davis, Joseph M. "Ashkenazic Rationalism and Midrashic Natural History: Responses to the New Science in the Works of Rabbi Yom Tov Lipmann Heller (1878-1654)." Science in Context 10 (1997): 605-626.
    • ---. "Philosphy and the Law in the Writings of R. Yom Tov Lipman Heller." In Studies in Medieval Jewish History and Literature, edited by Isadore Twersky and Jay Harris, 249-280. Harvard Judaic monographs 2. Cambridge, Mass: Harvard University Press, 1979.
    • ---. Yom-Tov Lipmann Heller: Portrait of a Seventeenth-Century Rabbi. Oxford: Littman Library of Jewish Civilization, 2004.
    • Eisikivits, Eliezer. "Fish Story." Mishpacha, 2009.
    • Slifkin, Nosson. The Camel, the Hare & the Hyrax: A Study of the Laws of Animals with One Kosher Sign in Light of Modern Zoology. Southfield, MI: Zoo Torah in association with Targum/Feldheim, 2004.