Abstract
Aquinas holds that human beings perceive material objects in a rational way, since their sensory faculty is always under the guidance of the rational faculty. This paper intends to shed light on this fundamental thesis. First, it examines the metaphysical background, focusing on Aquinas’s claim that there is just one soul with interconnected, hierarchically ordered faculties. Second, it looks at the interconnection in the case of perception, paying particular attention to the vis cogitativa. This special power, which can only be found in human beings, belongs to the sensory faculty but is always guided by the rational faculty and produces perceptions that are conceptually structured: it enables human beings to see something as something. Third, the paper builds a bridge to recent theories of “transformative rationality.” Like the advocates of this theory, Aquinas claims that rationality is not simply added to sensory activity, but rather something that is present in every act of human perception.