“pervasion” to mean that one of two accidents is located where the other is. This may be called sharing a location, interpenetration, coexistence, or the like. Accordingly, the conception of negation and the conception of affirmation coexist, just as other conceptions coexist. All conceptions have their locus in the locus of knowledge within the human being. They all share a location and coexist, subsisting in a single locus.

[Responses to al-Rāzī’s fifth argument: The first response]

It may be said:

The mere fact that the mind posits certain alternatives does not establish their possibility in external reality. For it may posit that a thing either exists, does not exist, or neither exists nor does not exist; that what exists is either necessary, possible, or neither necessary nor possible; and that it is either eternal or originated, either self-subsisting or subsisting in another, or neither self-subsisting nor subsisting in another. Yet these and similar suppositions do not establish that all these alternatives are possible in external reality.