Abstract

The text presented aims to illustrate the thesis of E. Gilson derived from his work “The Unity of Philosophical Experience” on the impersonal necessity linking philosophical ideas, as exemplified by Porphyry and his work Sententiae ad intelligibilia ducentes. E. Gilson puts forward a thesis that the philosopher is free at the moment of choosing the first principles of their philosophy, then they must accept the consequences that necessarily follow from these principles. Porphyry’s Sentences are a fairly synthetic account of Plotinus’ metaphysics and allow for a quite clear grasp of both the starting point and the above-mentioned consequences. In addition, for contrast, the paper presents the position of Alexander of Aphrodisias, similar in several points to that taken by Porphyry, but ultimately completely different.