Ser y Tiempo

This text is a Lecture given in La Sabana University (Bogota, Colombia) in August 1984. It address the topic of time from a metaphysical perspective, and for this considers necessary to use the modal logic. Compares between them the different positions of Leibniz, Hegel, Heidegger and Aristotle. Finally, it can be said that the best is the Aristotelian one, because he uses 4 modal notions, not three like the rest, and not identifies anyone with another, but distinguishes sufficiently everyone from the rest.