Rabbi Ezekiel Landau of Prague was one of the most respected halakhic authorities and communal leaders in eighteenth-century Europe. Like many rabbinic authors he is usually referred to by the title of his most famous book, the “Noda‘ Bi-Yhudah” [“In Judah he is known”], a collection of responsa that was published in two editions, in 1776 and 1811.
The latter volume was actually published posthumously by Ezekiel’s sons, one of whom, Samuel Landau, contributed a preface to the collection. In that preface Samuel spoke of his indebtedness to his illustrious father. This led him to discuss the various qualities that children inherit from their parents. In that context he expounded a saying of Rabbi Akiva from the Mishnah: “The father transmits to the son beauty, strength, wealth, wisdom and longevity.”
Rabbi Samuel had no problem with the premises that physical traits are transmitted by heredity, or that children are usually born into economic circumstances that were shaped by their parents. He was however bothered by the Mishnah’s implication that wisdom is inherited in a manner analogous to the genetic inheritance of physiological traits.
Now this objection could be easily resolved if we applied it to Torah education and scholarship: nobody would dispute that children who are raised in an environment of religious learning are far more likely to excel in their ability to master the intricacies of the traditional rabbinic curriculum. But Rabbi Landau preferred not to take this easy way out. He insisted that the Mishnah is not speaking only of religious learning, “but in other matters there is knowledge in all his ways, in all his endeavours.” Evidently he is applying the statement in a generic sense to a person’s inborn intelligence, in a way that makes it comparable to the traits of physical beauty and strength to which it is being juxtaposed.
This led the good rabbi to digress into some intriguing speculation about the physiological and chemical sources of human intelligence. For that purpose, he adduced data from the realm of biochemistry. He noted that scientists had broken down the contents of the human body into four main constituents: water, oil, lime and salt. Furthermore, he reported that experimental research revealed a fascinating fact—that the bodies of persons who were recognizable in their lifetimes for their intellectual acumen and higher intelligence contained a higher proportion of salt.
Now, Rabbi Samuel Landau was quite sympathetic, especially during his younger years, to the modernist trends that were taking root in European Judaism in his day. He supported Rabbi Moses Mendelssohn’s translation of the Bible into literary German and encouraged parents to provide their children with secular education. He also supported the publication of some introductory scientific texts translated into Hebrew by Enlightenment advocates. Nevertheless, his statements about the chemical composition of the human organism and the effects of salt remain surprising, to say the least.
I claim no expertise in the history of eighteenth- or nineteenth-century science, but I was unable to track down any authority, respectable or otherwise, who identified the ingredients that Rabbi Landau names. A more plausible approximation can perhaps be reached if we allow for the fact that Hebrew did not yet possess a consistent set of translations for chemical substances. Thus, what he called oil (shemen) might well refer to fats or proteins, and “limestone” to calcium and its compounds. This would not be totally removed from our current science that lists the body’s most common molecular types as water (at nearly 75%), protein, fats (or lipids), calcium (hydroxylapatite) and carbohydrates. Nevertheless, glaringly absent from the list are sodium, chlorine or sodium chloride [ = salt], which account for just 0.4% of the human body, whether of geniuses or others. Maybe Rabbi Landau misheard something that a doctor had told him.
Nonetheless there is a more indirect link between salt and intelligence levels. The practice of injecting iodine into consumer salt was introduced in the United States around 1924, primarily to prevent the widespread occurrence of goitre in midwestern states. The innovation also led to a 3.5% increase in the I.Q.s of those who were using iodized salt.
Many forms of natural salt do in fact contains small amounts of iodine, though not in sufficient proportions to produce the desired benefits. It seems possible (and I must again disclose my lack of credentials in the area) that—like so many foods that have had their nutrients processed out of them until we must artificially restore them through vitamin supplements and the like—the salt available in eighteenth-century Europe did contain enough natural iodine to affect intelligence to a degree that was apparent to scientists. It’s a long shot, but not impossible.
At any rate, Rabbi Landau was so delighted with his discovery that he used it to explain some additional passages in the Talmud. For example, the rabbis dealt with a situation where a father only had enough resources to provide an education for one person, and both parent and child were in need of learning. Whose claim is given priority? The sages ruled that the father has first claim, but Rabbi Judah added that if the son clearly demonstrates special educational potential, then he is given preference. The wording of Rabbi Judah’s stipulation is that the boy is “memullaḥ”—literally: salted.
The word memullaḥ is a familiar one to speakers of modern Hebrew. It is used as the equivalent of the English “seasoned” and is usually applied to shrewd traders. However, students of the Talmud in earlier times found it quite puzzling. The context in the Mishnah implies that it refers to intellectual acuity, but what does that have to do with salt? Rabbi Akiva Eiger had suggested an alternate reading there of: “memulla,” in the sense of “stuffed” with knowledge or virtues. That usage is attested in texts of the ethical treatise Derekh Eretz Zuṭa which states that “Torah scholars are accustomed to be humble, of lowly spirit, eager and memulla.”
Rabbi Landau defended the reading “memullaḥ” which he adduced as evidence for the rabbis’ acknowledgment that cleverness and understanding can result from a higher proportion of salt in a person’s physiological make-up.
Similarly, there are a number of places in the Talmud where a teacher offers to answer a student’s question “when you measure me out a kor of salt.” Rashi comments on some of these cases that the retort was meant tongue in cheek (presumably because it is inappropriate to accept a reward for sharing Torah insights). On the surface, this seems like an innocent example of the kind of menial chores that a disciple might have performed for his master in times when the acquisition of salt entailed more than removing a box from a shelf (in similar situations the talmudic demand involved carrying the teacher’s garments to the bath house). By noting the association between salt and wisdom (for which he provided additional examples), Rabbi Bezalel Zev Safran of Bacau, Roumania, was able to discern a more pointed symbolism to the saying, as implying: even if you were to elevate your intelligence by increasing your salt intake, you would not be able to solve this problem!
But not all mentions of salt in Hebrew texts are equal. Take for example the Hebrew word for sailor, “mallaḥ,” which appears to allude to the briny waves upon which they travel.
And yet linguists have shown that the word has nothing to do with salt. It originated in Sumerian and crept into biblical Hebrew via Akkadian. This is consistent with the fact that the ancient Israelites did not do much of their own maritime travel and relied on foreigners, especially the Phoenicians, for those services.
Like so many attractive theories, it is advisable to take these ideas about the mental benefits of salt with a grain of ...er, intelligence.