Any scholar would be pleased to have written a book that shaped all subsequent research on the same topic, becoming at once a standard reference and a guide for subsequent publications. One can only imagine how Dimitri Gutas must feel, having written two such books (or even three, if you include his pioneering Greek Wisdom Literature in Arabic Translation, 1975). His Greek Science, Arabic Culture (Routledge, 1998), a pivotal monograph on the Greek–Arabic philosophical translation movement, came a decade after Avicenna and the Aristotelian Tradition, which may have had an even more dramatic impact on the study of philosophy in the Islamic world. Consider three of the most important books on Avicenna to appear since the turn of the century: David C. Reisman's The Making of the Aristotelian Tradition (2002), Robert Wisnovsky's Avicenna's Metaphysics in Context (2003), and Amos Bertolacci's The Reception of Aristotle's Metaphysics in Avicenna's Kitāb al-Shifāʾ (2006). All bear the unmistakable signs of influence from Gutas, and they are just a few of the highlights from recent research on Avicenna, which has become the most active and sophisticated area within the field more generally. This is in stark contrast to the situation in 1988, when Gutas could complain of the “still waters” and “confused” state of research.

The appearance of a second edition of the book offers a chance to highlight its main contributions, among which I would list the following. First, there was Gutas' forthright rejection of certain misconceptions concerning Avicenna's intellectual profile. Notably, he was then (and is occasionally nowadays, but thanks to Gutas seldom) read as a deeply mystical author. Particularly important here was Gutas' demolition of the myths surrounding “eastern philosophy”, which Ibn Ṭufayl hailed as a true esoteric core of Avicenna's teachings. Gutas showed that, on the contrary, “eastern philosophy” was little more than a short-lived branding exercise for Avicenna's standard, non-mystical philosophy. Second and more positively, there was Gutas' nuanced account of Avicenna's stance towards Aristotle, which gives his book its title. Subsequent research has taken its lead from this account, according to which Avicenna was on the one hand engaged in a deep and sustained engagement with Hellenic philosophy and the works of Aristotle in particular; and on the other hand a self-consciously original thinker who had no hesitation in departing from Aristotle when he saw fit. This went hand-in-hand with a third achievement, namely Gutas' reconstruction of Avicenna's writing career, on the basis of a range of biographical texts made available in translation in the first chapter of the book and extensive research into the dating and circumstances of composition for the Avicennan corpus. While some details of Gutas' account have been disputed by scholars such as Yahya Michot, his picture has broadly stood up to scrutiny. Fourth and finally, there was Gutas' analysis of specific philosophical themes in Avicenna, especially in the area of epistemology. Chapter 3 offered a new assessment of the much misunderstood concept of ḥads (then translated by Gutas as “intuition”, now in the new edition with the more awkward but accurate “guessing correctly”). This part of the book spawned a whole mini-literature of its own. Revisiting Gutas' monograph has reminded me of the insights it offers even on thinkers other than Avicenna, for instance in a passage on Abū Bakr al-Rāzī's critique of prophecy (pp. 239–40) which rightly focuses on his polemic against taqlīd.

If only because it seems appropriate to a book about the famously critical Avicenna, I'd like to register a note or two of mild disagreement. I do not share Gutas' view that Avicenna should be seen as a “rationalist empiricist”, with an explicit comparison to modern empiricists like Locke (p. 375). In my view the famous “flying man” argument is offered precisely to show that the soul's existence to us is available without using the resources of “experience”. Rather self-awareness, which usually remains tacit, is presupposed as a condition prior to any possible experience. To some extent this may be simply a dispute over words: it's not clear to me what it would mean to say that our grasp of primary intelligibles like existence is “empirical”. It becomes a more substantive issue, though, when Gutas aligns Avicenna's project with that of the modern Empiricists. Translating mushāhada as “experience”, while justifiable in itself, is potentially misleading here. I think Avicenna's point in using it is to include the sort of cognition that would not be recognized by Empiricists like Hume or Locke. This is of course a relatively minor point. At a more general level, I tend to think that kalām played a larger role in Avicenna's intellectual development than emerges from Gutas' monograph. As he points out, the official Avicennan view is that kalām can be dismissed as mere dialectic. But then Avicenna is not known for acknowledging all his intellectual debts, and there is a case to be made that kalām offered an important foil and even a source for some of his central ideas in metaphysics.

That is just an illustration of the fact that a full assessment of Avicenna's intellectual formation remains a desideratum for future research. As it is, no book has constituted a larger step towards that goal than this one, which (in either edition) is far more than the “introduction” it modestly announces itself to be. Its wide-ranging influence is evident from the footnotes of the new edition, which incorporate references to the explosion of subsequent literature on Avicenna. (I wonder if Gutas would nowadays risk making the memorably provocative remark included in the original version, to the effect that if anything seems to be missing from his bibliography, then “the omission was deliberate”.) Still more useful are the addition of a substantial conclusion, which steps back and offers a general assessment of Avicenna's philosophical project, and a new inventory of Avicenna's authentic works, which by itself will be a crucial reference for future scholarship. In light of these new resources, even those who own the original book will want to acquire a copy of the second edition. Avicenna and the Aristotelian Tradition has a strong claim to be the most important study ever published on Avicenna, and the new version is a worthy and welcome update.