عنوان مقاله [English]
Franz Brentano was one of the most influential philosophers of the second half of nineteenth and early twentieth century. His major role in the history of philosophy can be shown through two aspects. One is that in virtue of his philosophy, we can make a link between the analytic and continental philosophies, and the other is that his doctrines and analyses can still be an origin for most of the philosophical investigations, as it was one century ago; although, because of the glorious personality of his direct and indirect students, his thoughts and insights have been not achieved immediately. Recent efforts in order to re-find and re-understand his philosophy show that Brentano has many valuable ideas in many different areas of philosophical investigations. These efforts show, more precisely, that his thoughts can still be a significant starting point for philosophical inquiry. Brentano’s works, like other influential philosophers’, covers a wide range of philosophical subjects including philosophical psychology, ontology, epistemology, syllogistic logic, ethics, philosophical theology, history of philosophy and many others. This article only focuses on the Brentano’s impact on syllogistic logic. His revision of formal logic has been done around the axis of a fundamental thesis according which all of the subject-predicate judgments should be reduced to existential judgments. We will explore, in this article, the procedure of this thesis development in Brentano’s thought and also its consequences for syllogistic logic. To have a complete understanding of Brentano’s revision of Aristotelian logic, it is required to have some acquaintances with several subjects not directly related to formal logic; e.g. ontology and epistemology.