ABSTRACT
The author focuses predominantly on the issue of the cognitive acts of the external senses, in the case of Francisco Suarez he include a treatment of the sensible species (likeness) of the internal sense. The author intend to present what he consider to be Nifo's main argument against Jandun's theory of the agent sense; second, the author aims to bring in Nifo's theory of the origin of the sensible species, which is supposed to replace the theoretical work that Jandun has assigned to the agent sense. According to Nifo, for Aristotle and Averroes the only agent in the production of sensation is the sensible species. Suárez shows that the sensible species of the internal sense, or the imaginative species (species imaginativa), cannot be efficiently caused by the sensible species of the external senses. In the case of the imaginative species we need a "lifter" of the sensible species of the external senses.
