The term “principle of sufficient reason” (PSR) was coined by Leibniz, and he is often regarded as its paradigmatic proponent. But as Leibniz himself often insisted, he was by no means the first philosopher to appeal to the idea that everything must have a reason. Histories of the principle attribute versions of it to various ancient authors. A few of these studies include—or at least do not exclude—medieval philosophers; one finds the PSR in Abelard, another finds it in Aquinas. And (...) while Leibniz retains pride of place in these histories, Spinoza is sometimes said to precede him “in appreciating the importance of the Principle and placing it at the center of his philosophical system.” In this paper, the author argues that the same should be said of the Islamic philosopher Avicenna. Writing 600 years before his early modern counterparts, Avicenna routinely and consistently appeals to the PSR in generating his metaphysical system. The paper aims first to establish that Avicenna deserves a position of prominence in histories of the PSR, and then to consider how he addresses certain challenges to the PSR, especially the threat posed by necessitarianism. (shrink)

The concept of efficient causation originates with Aristotle, who states that the types of cause include ‘the primary source of the change or rest’. For Medieval Aristotelians, the scope of efficient causality includes creative acts. The Islamic philosopher Avicenna is an important contributor to this conceptual change. In his Metaphysics, Avicenna defines the efficient cause or agent as that which gives being to something distinct from itself. As previous studies of Avicenna's ‘metaphysical’ conception of the efficient cause attest, it takes (...) God as a model agent. This essay considers whether Avicenna's ‘metaphysical’ conception of the efficient cause applies to natural agents. It ultimately argues that Avicenna offers a unified view of the efficient cause, which includes both divine and natural agents. On this view, an efficient cause gives being to another and is simultaneous with its effect. While Avicenna's defence of this view is an important chapter in the history of the concept of the efficient cause, it is also of interest in its own right. By appeal to a version of the principle of sufficient reason, it challenges a widespread view that causes are temporally prior to their effects. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Long Commentary on theDe Anima of AristotleKara RichardsonAverroes (Ibn Rushd) of Cordoba. Long Commentary on the De Animaof Aristotle. Translated with an introduction and notes by Richard C. Taylor, with Thérèse-Anne Druart, sub-editor. Yale Library of Medieval Philosophy. New Haven-London: Yale University Press, 2009. Pp. cix + 498. Cloth, $85.00.The Andalusian philosopher Ibn Rushd (d. 1198) had two names in the medieval Latin West: 'the Commentator', and 'Averroes'. (...) The first of these underscores his importance as an interpreter of Aristotle ('the Philosopher'). The second was modified at least once by the adjective 'accursed' (in Duns Scotus's Ordinatio, bk. 4, d. 43, q. 2). 'That accursed Averroes' refers to the person who held that there exists only one human intellect. Averroes defends this view—typically called the unicity doctrine—in his Long Commentary on Aristotle'sDe Anima.Richard C. Taylor's translation of the Long Commentaryis based on Crawford's 1953 edition of the medieval Latin text (the original Arabic text is extant only in fragments). Brief portions of this commentary, which relate directly to the controversial and influential unicity doctrine, have previously been translated into English. Taylor's complete translation makes available in English for the first time the whole account of the soul and its powers, of which the unicity doctrine is a part. The translation will benefit graduate or advanced undergraduate students of the history of philosophy, as well as non-specialist scholars who want to understand what all the fuss was about. Taylor also provides extensive notes, which contain, among other things, Averroes' sources, extant Arabic fragments corresponding to the Latin, and explanations of technical terms and dense argumentation. For these reasons alone, Taylor's work must be considered a significant contribution to scholarship in the history of philosophy. There is also a lengthy introduction that presents the state of research on Averroes' psychology.Readers of Aristotle are familiar with his distinction, in De Anima3.5, between intellect in its passive role as a receiver of intelligibles and intellect in its active role as a maker of intelligibles. Averroes' unicity doctrine is remarkable as an interpretation of the passiveintellect, which is called the "material intellect" by analogy with prime matter (like prime matter, the material intellect can, in its own way, receive any form). To advocate the unicity of the activeintellect is not so remarkable. The latter view was standard in the Arabic tradition, which inherited it from Greek commentators on Aristotle. Those who affirm the unicity of the active intellect may hold the material intellect to be a power for receiving intelligibles [End Page 398]that is ultimately brain-based. Or they may hold the material intellect to be the supreme cognitive power of incorporeal human souls, which are multiplied in accordance with the number of human bodies. Averroes' defense of the unicity of the material intellect in the Long Commentaryinvolves a principled rejection of each of these alternative views, as well as a novel account of the role of intellect in human cognition. Taylor's introduction treats the development of Averroes' unicity doctrine and adjudicates a dispute about the dating of his Middleand Longcommentaries on the De Anima. Based in part on a comparison of portions of the Long Commentaryidentical to portions of the Middle Commentary, Taylor argues that the Long Commentaryis most likely the later work. These passages are identified in the notes to the translation.The introduction also provides a brief exegesis of the Long Commentary. This section explains the reasons behind the unicity doctrine, but misses the opportunity to highlight other points of interest in Averroes' psychology. Moreover, it leaves unaddressed certain questions likely to be pressing for newcomers to the text. For example, the unicity doctrine entails the denial that intellect is the seat of individual consciousness; so how would Averroes explain individual consciousness? What role, if any, does consciousness play in his account of cognition?Finally, Taylor's introduction includes a useful survey of Averroes' sources and a brief account of the influence of the Long Commentary, especially in the Latin West, which puts to rest the... (shrink)