Multiple generalization for single entity

I need to select System.Image and System.FileDocument Generalization for single entity . Currently I can able to select only one generalization but i need to select both the generalization, is it possible to do that , if not what is the alternate solution
1 answers

As Thijs Schoemaker mentioned, System.Image is a specialized entity of System.FileDocument. 

So, when you set System.Image as Generalized object, then it is already a FileDocument. 

Not sure, why you want to set for both entities. And it is not possible. 

Reconsider your domain modelling.