sensus communis a cognitive faculty to which the five senses report. It was first argued for in Aristotle’s On the Soul II.1–2, though the term ‘common sense’ was first introduced in Scholastic thought. Aristotle refers to properties such as magnitude that are perceived by more than one sense as common sensibles. To recognize common sensibles, he claims, we must possess a single cognitive power to compare such qualities, received from the different senses, to one another. Augustine says the ‘inner sense’ judges whether the senses are working properly, and perceives whether the animal perceives (De libero arbitrio II.3–5). Aquinas (In De anima II, 13.370) held that it is also by the common sense that we perceive we live. He says the common sense uses the external senses to know sensible forms, preparing the sensible species it receives for the operation of the cognitive power, which recognizes the real thing causing the sensible species. See also AQUINAS, ARISTOTL. J.Lo.