Person does not want (to) Mortality. Person wants (to) Special. Special is related to Case. 
Age is related to Life. Life is a synonym of Existence. Existence is the opposite of Absence. 
Mortality <--NotDesires-- Person --Desires--> Special <--RelatedTo--> Case 
Age <--RelatedTo--> Life <--Synonym--> Existence <--Antonym--> Absence 