The Tzemach David

Note the goose emerging from the Star of David on the tombstone of David Gans (1541-1613)

The Tzemach David

People Of The Book:  Classic Works Of The Jewish Tradition

(This article originally appeared in the Five Towns Jewish Times on February 11, 2016.)

David Gans (1541–1613) was a scientist and a rabbi in an age when the dual pursuit of these intellectual passions was a life-threatening occupation. He studied Torah under Rabbi Moshe Isserles in Cracow and the Maharal of Prague, and his expertise in astronomy was so formidable that he collaborated with Johannes Kepler and Tycho Brahe.

Rabbi Gans made a signal contribution to this field by translating the Alphonsine tables from Hebrew into German. Originally compiled in 1252 by a commission of Jewish and Muslim scholars for King Alphonso X, the Wise of Spain, these navigational charts were essential to the seafaring nation, and Jewish astronomers had been updating them for centuries in Hebrew. (Columbus relied on the version prepared by Joseph Vecinho, one of many Jewish contributions to the discovery of the New World.)

Despite the obvious advantages of the emerging scientific wisdom of the era, the Catholic Church reacted with a terrifying fanaticism, burning Converso Jews and Christian scientists alike for suggesting that the earth revolved around the sun. Even the supposedly more moderate Protestant Church arrested Kepler’s aged mother and tried her as a witch.

The work of David Gans, by contrast, illustrates the scope of academic freedom in the Jewish world. Following Maimonides, the bulk of Jewish thinkers favored the establishment Ptolemaic vision of a flat earth surrounded on all sides by water, with a heavenly parade of celestial orbs circling this stable center. Scattered early references to the spherical shape of the world, however, were increasingly confirmed by the age of exploration, including the remarkably prescient passage in the Zohar III 10a: “The earth is round as a globe . . . Revolutions make it daytime in one half and night in the other . . . There are places where it is perpetually light and places where it is perpetually dark.” Gans did not completely accept all the implications of the new Copernican, heliocentric model, but he engaged fully in the intellectual commerce of the late 16th and early 17th centuries with a refreshing open-mindedness tempered by traditional learning.

His most important contribution to Jewish studies is the highly original Tzemach David (“Shoot of David,” 1592). As fascinated by history as he was by science, he composed a one-volume history of the world, divided into two parts. The first explored the history of the Jews from Adam to the late 16th century, relying heavily on the limited historical studies produced till then, such as the ancient work of Josephus and the medieval Hebrew version, Yosippon. The second and larger section is a survey of world history, using secular calendars. Interestingly, he defends his work as appropriate Sabbath reading, relying on the ruling of his early master the Rema in Orach Chaim 307:1.

By modern standards, Tzemach David is more of a chronicle than a history, with the events presented simply in linear, chronological format with limited interpretive content. The bifurcation of Jewish and secular history is reflective of a Jewish Weltanschauung common even today: Jews move in history, but are not of history, a view that modern historians consider as retrograde as Ptolemaic astronomy. Nevertheless, Tzemach David is a pioneering work, especially valuable for the study of Ashkenazic Jewish history.

David Gans is also known for his popularization of the six-pointed Star of David, a symbol first associated with the Jews of Prague some 100 years prior. (The legends that the Magen David decorated the shields of King David’s troops have no literary basis.) Gans saw in the star, with its repeating symmetries of two overlapping equilateral triangles, a symbol for the mathematical perfection of G‑d’s universe. His gravestone in Prague is thus proudly adorned with a Magen David, surmounted by a line drawing of a goose: his family name in Hebrew was Avuz, translated into German as Gans (goose).

This article originally appeared in the Five Towns Jewish Times on February 11, 2016.

Who Was Rabbi David Gans?

David Gans (1541-1613) was a Rabbinic scholar, historian, and astronomer.  A student of Rabbi Moshe Isserles and the Maharal of Prague, he collaborated actively with Tycho Brahe and Johannes Kepler and left behind important scholarly works.


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