The second volume of Jonathan Barnes' papers on ancient philosophy contains twenty-seven pieces under the broad heading of Logic. The essays were written over a period of some forty years. Some of them were published in obscure places (and two or three of them in a foreign language). The French essays have been done into English; and all the essays have been retouched, and a few of them substantially revised.The first three essays in the volume are of a general nature, being concerned with ancient views on the status of logic--and with the distinction between formal and material inferences. The next nine items deal with different aspects of Aristotelian logic--the copula, negation, the categories, homonymy, and the principle of contradiction. Then come three papers about the connection (or lack of connection) between Aristotelian logic and Stoic logic. Two of the pieces discuss Theophrastus' theory of 'hypothetical' syllogisms. After that, things run more or less chronologically--a short notice on the Dialecticians, three essays on aspects of Stoic logic, a pair of papers on ancient theories of meaning, items on adverbs and connectors, on Philoponus and Boethius, and on an anonymous tract written in the autumn of 1007 AD. All in all, there is matter to divert scholars and students of ancient philosophy.