Full Idea
Mental files are entries in the mental encyclopedia, that is, concepts. Some, following Grice, say they are information collections, but I think of them as containers. Collections are determined by their elements, but containers have independent identity.
Gist of Idea
Mental files are concepts, which are either collections or (better) containers
Source
François Recanati (Mental Files in Flux [2016], Pref)
Book Reference
Recanati,François: 'Mental Files in Flux' [OUP 2016], p.-12
A Reaction
[compressed] [Grice reference is 'Vacuous Names' (1969)] I agree with Recanati. The point is that you can invoke a file by a label, even when you don't know what the content is.