Alexander of Aphrodisias, who flourished c. 200AD, was the leading Peripatetic philosopher of his age. Most of his philosophical energies were spent in commenting upon Aristotle: his commentary on the Prior Analytics remains one of the most thorough and helpful guides to this difficult work; in addition, the commentary preserves invaluable information about various aspects of Stoic logic, and it also presents a picture of categorical syllogistic at a turning point in its historical development. This volume contains a translation of the first third of the commentary - the part dealing with non-modal syllogistic. The translation is preceded by a substantial introduction which discusses Alexander's place in the commentatorial tradition and his use of logical terminology. The book is completed by a translation of the pertinent part of the Prior Analytics, a summary account of categorical syllogistic, and a set of indexes.

In the second half of book 1 of the Prior Analytics, Aristotle reflects on the application of the formalized logic he has developed in the first half, focusing particularly on the non-modal or assertoric syllogistic developed in the first seven chapters. These reflections lead Alexander of Aphrodisias, the great late second-century AD exponent of Aristotelianism, to explain and sometimes argue against subsequent developments of Aristotle's logic and alternatives and objections to it, ideas associated mainly with his colleague Theophrastus and with the Stoics. The other main topic of this part of the Prior Analytics is the specification of a method for discovering true premises needed to prove a given proposition.Aristotle's presentation is sometimes difficult to follow, and Alexander's discussion is extremely helpful to the uninitiated reader. In his commentary on the final chapter translated in this volume, Alexander provides an insightful account of Aristotle's criticism of Plato's method of division.

The last 14 chapters of book 1 of Aristotle's "Prior Analytics" are concerned with the representation in the formal language of syllogistic of propositions and arguments expressed in more or less everyday Greek. In his commentary on those chapters, "Alexander of Aphrodisias" explains some of Aristotle's more opaque assertions and discusses post-Aristotelian ideas in semantics and the philosophy of language. In doing so he provides an unusual insight into the way in which these disciplines developed in the Hellenistic era. He also shows a more sophisticated understanding of these fields than Aristotle himself, while remaining a staunch defender of Aristotle's emphasis on meaning as opposed to Stoics concern with verbal formulation. In his commentary on the final chapter of book 1 Alexander offers a thorough discussion of Aristotle's distinction between denying that something is, for example, white and asserting that it is non-white.

The commentary of Alexander of Aphrodisias on Aristotle's Prior Analytics 1.8-22 is a very important text, being the main ancient commentary with chapters in which Aristotle invented modal logic - the logic of propositions about what is necessary or contingent (possible). The first volume of Ian Mueller's translation covered chapters 1.8-13, and reached as far as the chapter in which Aristotle discussed the notion of contingency. In this, the second volume, the 'greatest' commentator, Alexander, concludes his discussion of Aristotle's modal logic. Aristotle also invented the syllogism, a style of argument involving two premises and a conclusion. Modal propositions can be deployed in syllogisms, and in the chapters included in this volume Aristotle discusses all the syllogisms containing at least one contingent premiss. In each volume, Ian Mueller provides a comprehensive explanation of Alexander's commentary on modal logic as a whole.

The commentary of Alexander of Aphrodisias on Aristotle's Prior Analytics 1.8-22 is the main ancient commentary, by the 'greatest' commentator, on the chapters of the Prior Analytics in which Aristotle invented modal logic - the logic of propositions about what is necessary or contingent (possible). In this volume, which covers chapters 1.8-13, Alexander of Aphrodisias reaches the chapter in which Aristotle discusses the notion of contingency. Also included in this volume is Alexander's commentary on that part of Prior Analytics 1.17 which explains the conversion of contingent propositions (the rest of 1.17 is included in the second volume of Mueller's translation). Aristotle also invented the syllogism, a style of argument involving two premises and a conclusion. Modal propositions can be deployed in syllogism, and in the chapters included in this volume Aristotle discusses syllogisms consisting of two necessary propositions as well as the more controversial ones containing one necessary and one non-modal premiss. The discussion of syllogisms containing contingent propositions is reserved for Volume 2. In each volume, Ian Mueller provides a comprehensive explanation of Alexander's commentary on modal logic as a whole.

Mantissa is the fourth (and last) volume of Jonathan Barnes' collected essays on ancient philosophy. It contains twenty-three papers on a diverse range of subjects, from the size of the sun to Plato and Aristotle in Victorian Oxford. One of the essays is new, and the others are all retouched or revised; six are newly translated into English.

The philosopher Abu Nasr al-Farabi (c. 870-c. 950 CE) is a key Arabic intermediary figure. He knew Aristotle, and in particular Aristotle's logic, through Greek Neoplatonist interpretations translated into Arabic via Syriac and possibly Persian. For example, he revised a general description of Aristotle's logic by the 6th century Paul the Persian, and further influenced famous later philosophers and theologians writing in Arabic in the 11th to 12th centuries: Avicenna, Al-Ghazali, Avempace and Averroes. Averroes' reports on Farabi were subsequently transmitted to the West in Latin translation. This book is an abridgement of Aristotle's Prior Analytics, rather than a commentary on successive passages. In it Farabi discusses Aristotle's invention, the syllogism, and aims to codify the deductively valid arguments in all disciplines. He describes Aristotle's categorical syllogisms in detail; these are syllogisms with premises such as 'Every A is a B' and 'No A is a B'. He adds a discussion of how categorical syllogisms can codify arguments by induction from known examples or by analogy, and also some kinds of theological argument from perceived facts to conclusions lying beyond perception. He also describes post-Aristotelian hypothetical syllogisms, which draw conclusions from premises such as 'If P then Q' and 'Either P or Q'. His treatment of categorical syllogisms is one of the first to recognise logically productive pairs of premises by using 'conditions of productivity', a device that had appeared in the Greek Philoponus in 6th century Alexandria.

The late Mario Mignucci was one of the most authoritative, original, and influential scholars in the area of ancient philosophy, especially ancient logic. Collected here for the first time are sixteen of his most important essays on Ancient Logic, Language, and Metaphysics. These essays show a perceptive historian and a skillful logician philosophically engaged with issues that are still at the very heart of history and philosophy of logic, such as the nature of predication, identity, and modality. As well as essays found in disparate publications, often not easily available online, the volume includes an article on Plato and the relatives translated into English for the first time and an unpublished paper on De interpretatione 7. Mignucci thinks rigorously and writes clearly. He brings the deep knowledge of a scholar and the precision of a logician to bear on some of the trickiest topics in ancient philosophy. This collection deserves the close attention of anyone concerned with logic, language, and metaphysics, whether in ancient or contemporary philosophy.

The so-called eighth Stromateus (‘liber logicus’) by Clement of Alexandria (d. before 221 C.E.) is an understudied source for ancient philosophy, particularly the tradition of the Aristotelian methodology of science, scepticism, and the theories of causation. A series of capitula dealing with inquiry and demonstration, it bears but few traces of Christian interests. In this volume, Matyáš Havrda provides a new edition, translation, and lemmatic commentary of the text. The vexing question of the origin of this material and its place within Clement’s oeuvre is also addressed. Defending the view of ‘liber logicus’ as a collection of excerpts made or adopted by Clement for his own (apologetic and exegetical) use, Havrda argues that its source could be Galen’s lost treatise On Demonstration.