Ens imaginarium: Kant e Wolff

The present article clarifies Kant's use of the expression ens imaginarium by confronting this use, on the one hand, with the traditional (which is still present in Leibniz), and, on the other hand, with Wolff's use. After considering the revival of the debate on the distinction between "imaginary" and "real" after the publication of the correspondence between Leibniz and Clarke ( 1), the article illustrates Wolff's transformation of the traditional concept of ens imaginarium, a transformation carried out through the theory of imaginary notions ( 2). Contrary to the fictitious ens, Wolff's ens imaginarium can work as a surrogate of the real ens, and thus play a heuristic function. In Kant, however, the expression ens imaginarium keeps the more traditional sense of "not real": space and time are imaginary beings if we conceive them as contents of the representation, rather than as pure forms of it ( 3). Thereby, Kant aims to oppose precisely the changes introduced by Wolff, which he considers incompatible with the a priori character of the concepts of space and time ( 4).