Josef ibn Kaspi's Retukot Kesef

Hebrew Linguistics and Biblical Exegesis from a Logician’s Point of View


  • Moshe Kahan


Joseph ibn Kaspi, Retukot Kesef, Sharshot Kesef, Tsror ha-Kesef, Hebrew linguistics, Middle Ages, philosophy, Maimonides, Alfonso de Zamora, Provence, RaDak, David Kimhi, Yonah Ben Janāḥ, Sefer HaShorashim


Josef ben Abba Mari ibn Kaspi is one of the radical philosophers that were Maimonides' disciples and followers, active in Provence in the 13th century. Kaspi composed two commentaries on Maimonides' The Guide for the Perplexed, one esoteric and one exoteric.

Three of Kaspi's biblical commentaries deal with linguistics in general and Hebrew linguistics in particular: Tzeror ha-Kesef, a summary of the Aristotelian Organon, which deals with general linguistic concepts as well; Retuqot Kesef, a logical-linguistic treatise in which Kaspi applies the laws of logic on the Hebrew language; Sharshot Kesef, a Hebrew-Hebrew dictionary based on Retuqot, whose purpose is to explain the Hebrew roots by the laws of logic, unlike the classical dictionaries prevalent at the time. The most original of the three, and the least researched so far, is Retuqot Kesef.

This article points out the unique structure of Retuqot, as suggested by Kaspi's introduction, and aims to describe how logical concepts are applied on Hebrew linguistics and biblical philology. This article focuses on the theory of motion. In the article I investigate how Aristotle perceives motion and survey the views of Al-Farabi and other Arab philosophers that wrote on this notion, as well as Maimonides'. Finally, I focus on Josef Kaspi and demonstrate how Kaspi employed the theory of motion in order to change the grammatical and philological perceptions common in his time.