conceptual

  I. Introduction Before he reached his mature metaphysical view of being as gradual in the  Republic   (Allen 1961) , Plato claims that neither can negative facts explain positive facts, nor vice versa  ( Phaedo  103b) (this is very likely a corollary of  his principle of opposites  according to which if  A  and  B  are of opposite ontological categories,  A  cannot explain  B  ( González-Varela and Barceló  2 023 ). Paulo Sergio Méndoza just informed me (on January 2024) that Kant held a similar ontological principle in his A  New  Explanation  of the  First  Principles of Metaphysical Knowledge   (September 27, 1755). Yet, it seems obvious that we explain positive facts by appealing to negative facts and vice versa, all the time. We say things like " Pat must be sick, because she would not have missed the party otherwise", "The Plant died because we forgot to water it", " The...