Abstract: Many scholars remain perplexed by Aquinas’s treatment of “mysterious” common natures. They call it “careless,” “contradictory,” or “ad hoc.” But the standard interpretation (adopted by authors such as Owens, Black, Kenny, Pasnau, Brower, and Galluzzo) mistakenly conflates the common nature with the nature absolutely considered. Starting from Boethius’s meaning of “nature” as whatever can in any way be intelligible, the author argues that the “common nature” and “nature absolutely considered” are conceptually distinct for Aquinas. Unlike the nature absolutely considered, the common nature positively has unity, existence, as well as the intention of universality. Moreover, the common nature (such as the nature of a species) is the only nature that is individuated. It exists in the individual “objectively,” as the foundation for human cognition.
Gaston Lenotre (Sat,) studied this question.