Summa of Philosophy According to the Mind of the Angelic Doctor St. Thomas Aquinas - Logic, Part I, Volume I - Salvatore Maria Roselli

This first volume begins Roselli’s Summa of Philosophy, an ordered presentation of Thomistic philosophy intended to synthesize and teach the principles of classical scholastic thought in accordance with Thomas Aquinas.

The work opens with logic as the foundational discipline of philosophy, presenting it as the art and science of correct reasoning directed toward truth. Roselli explains the structure of intellectual activity through the analysis of concepts, propositions, and arguments, emphasizing the role of logic as an instrument for all higher sciences.

He treats key topics such as terms and their properties, definition, division, judgment, and syllogistic reasoning. Special attention is given to the laws of thought and the proper method of scientific demonstration, showing how valid inference depends on the conformity of the mind to reality.

Throughout the volume, Roselli maintains a clear scholastic and pedagogical approach, aiming to provide a structured introduction to rational inquiry. Logic is presented not as a purely formal system, but as the necessary foundation for metaphysics, natural philosophy, and theology within the Thomistic framework.