The Object of the Sensus Communis is not the Common Sensible
Considering the proper and the common sensibles as discrete objects of direct sensation rules out the possibility of confusion over the function of the sensus communis. One might be led to claim, however, that the sensus communis is that faculty by which the common sensibles are perceived. There are indications that Aristotle believed that the common sensibles were the direct objects of awareness of the sensus communis. Turnbull once offered this interpretation of Aristotle: ‘I may also note that the Aristotelian “common sense” is especially the faculty for perceiving the common sensibles [. . .].’ What is interesting here is that Turnbull, at the end of this analysis, indicates the position of common sensible noted above: ‘[the] common sensible is available in more than one sense modality and not mostly in sight.’ Everson too holds this position, arguing that for Aristotle the common sensibles are the objects of the sensus communis and are perceptible by the external senses only ‘qua the common sense’.
In commenting on this discussion, Pasnau notes that Albertus Magnus shared this controversial reading of Aristotle. However, Aquinas, Pasnau correctly claims, had ‘no doubt that the common sensibles are perceived per se by the external senses’.
The argument articulated in this study is that while Aquinas holds the second position noted above by Turnbull, he does not hold the first. The sensus communis does not have as its per se object the common sensibles. This claim would make sense only if the sensus communis were looked at as the ‘root’ of every act of sensation. But then the proper sensibles too would be the objects of the sensus communis. The difference between Aristotle and Aquinas here may be in the interpretation of the ‘root’ function for the sensus communis. Furthermore, even if Aristotle held this position on the common sensibles being the object of the sensus communis, this is unequivocally not the position adopted and put forward by Thomas Aquinas. Aquinas appears to consider the opposite position not found in Aristotle’s texts either. In support of this line of argument, one finds the following passage in the Commentary:
Aristotle rejects the suggestion that the ‘common sensibles’ are an object of another and distinct sense. For the proper and direct object of any one sense is only known indirectly by any other sense. But the common sensibles are not known indirectly by any sense at all. Rather, they are each directly known by several senses. Therefore, they cannot be the proper objects of any one sense. (Commentary on the Soul, no. 575)
The same argument is put forward in the following passage from the Commentary: ‘[The common sensibles . . .] are a common yet direct obj ect of several distinct senses. It follows that they answer to no special and distinct sense’ (no. 580). These texts have established, therefore, that the common sensible is not the per se object of the sensus communis as this internal sense faculty is construed by Thomas.
-  Turnbull, ‘The Role of the “Special Sensibles”’, 15. 19 Ibid., 25-6.
-  20 Stephen Everson, Aristotle on Perception (Oxford: Clarendon Press, 1999), 148-57.
-  21 Rescher offers a similar interpretation: ‘Medieval scholasticism introduced a different sort of sensuscommunis [Rescher uses ‘sensus commonia] by contrasting the outer senses (sight, touch, hearing, etc.)with an inner sense capable of apprehending matters about which two or more senses can inform us incommon even as the shape of the sugar cube can be revealed, both by sight and by touch. Clearly the apprehension of such commonality is not revealed by any of the outer senses themselves, but requires a differentcapacity for its apprehension, and thus access to sense-commonality was characterized as sensus commu
-  nis’: Nicholas Rescher, Common-Sense: A New Look at an Old Philosophical Tradition (Milwaukee, Wis.:Marquette University Press, 2005), 239, n. 24.
-  Robert Pasnau, Thomas Aquinas on Human Nature: A Philosophical Study of Summa Theologiae, 1a75-89 (Cambridge: Cambridge University Press, 2002), 432, n. 23.
-  Aquinas, furthermore, had the benefit of reading the Aristotelian commentaries by Avicenna andAverroes.