Isaac Husik, “Judah Halevi,” A History of Medieval Jewish Philosophy, Jewish Publication Society, 1944, pp. 150–183.  

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“A noted scholar elucidates the distinguishing characteristics of the works of several Jewish thinkers of the Middle Ages. In addition to summaries of the main arguments and teachings of Moses Maimonides, Isaac Israeli, Judah Halevi, Abraham Ibn Daud, Hillel ben Samuel, Levi ben Gerson, and others, the author offers insightful analyses.”

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