Marcos Louis D. Catalan, Jr., S.J. (“Human Sentient Intelligence in the Philosophy of Xavier Zubiri”) writes an essay on Xavier Zubiri’s concept of sentient intelligence (inteligencia sentiente). For Zubiri, what differentiates humans from animals is sentient intelligence. Its formation is tied to the genetic growth of nerve cells and increasing centralization of the nervous system—an organic process that makes up the faculty of sensibility. The production of an excess in the number of neurons with short axons causes a further structuring of the faculty of sensibility with intelligence which already exists in potency in the embryo. The result of this psycho-organic process is sentient intelligence, which is the capacity of the human person to apprehend things as realities. Zubiri, whose writings have wide currency with and influence on Spanish-speaking intellectuals, has endeavored to reformulate classical metaphysics (rational psychology) in a language that is consistent with science in his time. Thanks to Catalan’s essay, our readers can have some glimpse of Zubiri’s originality.