According to Aristotle’s De anima, human senses can recognize individual things qua individuals. This implies that they can apprehend individual forms, i.e., substances. However, substance is not sensible in itself. Although incidental perception accounts for the connection between intellectual and sensible properties, the question remains how intellect-lacking animals can perceive individual things. Avicenna advances an inner-sense theory to explain how animals interact with individuals without…
Read moreAccording to Aristotle’s De anima, human senses can recognize individual things qua individuals. This implies that they can apprehend individual forms, i.e., substances. However, substance is not sensible in itself. Although incidental perception accounts for the connection between intellectual and sensible properties, the question remains how intellect-lacking animals can perceive individual things. Avicenna advances an inner-sense theory to explain how animals interact with individuals without perceiving substance. Averroes’s belief that the human senses grasp the intentio individualis, i.e., the individual substantial form, presupposes that animal and human senses are different. Albert the Great’s solution, in his Commentary on the De anima, retains Averroes’s intentio individualis but agrees with Avicenna’s claim that rational and non-rational animals share identical sensitive apparatuses. Albert arrives at his solution in three main steps. First, he redefines the concept of abstraction from Avicenna’s Liber de anima, part II, chapter 2, to separate the individual thing from its signification, i.e., its intention. Secondly, he applies his forma totius theory asserting that each of the five Porphyrian universals can be predicated of an individual thing because they refer to the totality of that thing. Thirdly, he uses the concept of praedicatio per se tertio modo from Posterior Analytics to argue that the Porphyrian universal accident refers to the totality of an individual thing. The resulting theory makes it possible to explain how the senses can apprehend the individual thing qua individual without the necessity of perceiving its substance.