Skip to main content



THEMISTIUS ° (317–c. 388 c.e.), statesman, rhetorician, and philosopher, known to medieval Jewish philosophers as a major interpreter of Aristotle; the author of commentaries which Maimonides recommends highly (see Maimonides' letter to Samuel ibn Tibbon, in S. Pines' introduction to his translation of The Guide of the Perplexed (1963), lix).

Themistius lived in Constantinople most of his life. A pagan, he held the office of senator and even prefect in the new Christian capital, and celebrated its emperors in several panegyrics. The pliant nature of Themistius' personality is also evident in his philosophical writings, in which he shows familiarity with the various currents of Greek philosophy and, in the tradition of late Greek thought, he believes Plato and Aristotle to be in substantial agreement.

Only two of Themistius' commentaries were translated into Hebrew (from earlier Arabic translation): his paraphrase of Aristotle's De caelo by Zerahiah b. Isaac *Gracian, in 1284; and his paraphrase of Book 12 of the Metaphysics by Moses ibn *Tibbon, in 1255 (both edited by S. Landauer, Commentaria in Aristotelem Graeca, 4 (1902), 1–167; 5 (1903), 1–35). Themistius' other commentaries, to the Prior and Posterior Analytics, the Physics, and De anima, were known either through Arabic translations or through secondary sources. He is often quoted by other late Hellenistic writers, notably John Philoponus, and by Islamic philosophers, particularly *Averroes. It is through supercommentaries to Averroes' writings that Themistius' views often find expression in the works of such late medieval Jewish figures as Levi b. Gershom and Moses of Narbonne.

Themistius' own contribution to Peripatetic philosophy lies in the interpretation, not completely consistent, which he gave to Aristotle's doctrine of the *intellect. He considered the "potential intellect" of Aristotle to be an independent, separate substance, though closely related, as matter is to form, to the similarly separate "agent intellect." He saw the intellect's bridge to corporeal forms and to man as accomplished through a "common," "passive intellect," neither separate nor immortal. Averroes was later to build upon this notion of an independent political intellect, identifying its substance completely with the universal Agent Intellect.


Pauly-Wissowa, 2nd series, vol. 5 (1934), s.v.Themistes; Steinschneider, Uebersetzungen, 125, 176; F.E. Peters, Aristoteles Arabus (1968), 16, 18, 34, 36, 42, 52; O. Hamelin, La théorie de l'intellect (1953), 38–43, 58–72.

[Alfred L. Ivry]

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Themistius°." Encyclopaedia Judaica. . 20 Feb. 2019 <>.

"Themistius°." Encyclopaedia Judaica. . (February 20, 2019).

"Themistius°." Encyclopaedia Judaica. . Retrieved February 20, 2019 from

Learn more about citation styles

Citation styles gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, cannot guarantee each citation it generates. Therefore, it’s best to use citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

The Chicago Manual of Style

American Psychological Association

  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.