BOOK REVIEWS 249 larger sections of the work will be translated-preferably not from the Latin, but from the Arabic original. JOSEPHL. B~u Columbia University Commentary on the Metaphysics of Aristotle. By St. Thomas Aquinas. Trans. by John P. Rowan. (Chicago, Illinois: Henry Regnery Company, 1961. Pp. xxiii + 955.2 vols., boxed, $25.00.) Generally speaking, the two Summae of St. Thomas, long available in English translation, contain all that is most personal and most profound in his philosophical thought. Nonetheless, it is quite impossible to get a fully adequate conception of St. Thomas' place in the history of western thought from a consideration of his theological writings alone. Hence, by translating St. Thomas' Commentary on the Metaphysics of Aristotle into English, Professor J. P. Rowan has provided the non-Latin reading student of the history of philosophy an invaluable service. For it is in his r61e as Aristotelian commentator that we see St. Thomas creating for the Schoolmen a version of Aristotle which served to render the Stagirite's thought into terms which became fundamental to the philosophical defense of Christianity. Further, by keeping in mind the fully-developed notions of St. Thomas on the existence of God and the nature of being as these are given us to understand in the Summae, the reader becomes better enabled, by a critical reading of Thomas' Commentary, to grasp the sense in which the Saint's theological writings are said by his enthusiasts to represent a "completing" and "perfecting" of Aristotle's thought. Professor Rowan's translation is based upon the Turin, 1950, edition of R. M. Spiazzi. This edition is itself fundamentally the older edition of M. R. Cathala, containing but few emendations. Although the translator was obliged to check Spiazzi occasionally against the Parma and Viv6s editions of Thomas' Opera Omnia, the usefulness of such consultation was, as Professor Rowan himself states, "limited inasmuch as both the editions of Viv~s and that of Cathala use Parma as their basic text" (p. vii). Further, since the edition from which he worked was not critical, Professor Rowan found it necessary in some instances to himself emend the reading of the Spiazzi text. However, where such alterations were made, and where indeed they were not obviously required, Professor Rowan indicated his iustification for the change in a footnote. It is unfortunate that no critical edition of Thomas' work was available to his translator; still, although a final evaluation of his emendations must, of course, attend the future appearance of a critical edition of Thomas' work, so far as we were able to judge, Professor Rowan's 250 HISTORY OF PHILOSOPHY changes were in all instances quite reasonable and well ]ustified. Professor Rowan has wisely included a translation of that version of the Aristotelian text upon which St. Thomas (in all probability) based his commentary . As this Latin version frequently departs from such currently available English translations as those of W. D. Ross, H. Tredennik, and others which are based upon Greek sources, a good deal of confusion as to Thomas' actual point of departure would have been introduced had this inclusion not been made. The general value and utility of Professor Rowan's work is further increased by his footnoted indications of the more important variations obtaining between the Greek text (as given in Bekker), and the Latin version employed by St. Thomas. For the reader who wishes to compare the Latin version, the Greek text, and the English translations, Professor Rowan has provided the standard Bekker reference numbers at the beginning of each of Thomas' Lectiones. To further simplify the whole matter of reference and cross-reference, Professor Rowan has used the letter C, followed by a numeral, to designate sections of Thomas' Commentary. These sections are the same as those established originally by Cathala. Numbers not preceded by C designate the appropriate sections of the Latin version of Aristotle's text, and correspond with those given by Spiazzi in his revision of the Cathala edition. Thus, as example, in such a reference as (241:C345), the first number designates the section of the version of Aristotle employed by St. Thomas, and the second, the section of St. Thomas...