Prescription is a type of Document. Patent is a type of Document. Patent is a type of Change. 
Purpose is related to Kill. Kill is related to Violence. Violence is related to War. War is related to Killing. 
Prescription --IsA--> Document <--IsA-- Patent --IsA--> Change 
Purpose <--RelatedTo--> Kill <--RelatedTo--> Violence <--RelatedTo--> War <--RelatedTo--> Killing 