Intersection of definitions

[Ezibenroc]

The question What are COBOL and Fortran? gives a nice triple: (COBOL,definition,?)∩(Fortran,definition,?).

Same idea for "Who are Barack Obama and George Bush?".

It would be nice that we return programming language in the first case, and president of the United States in the second.

A solution could be to return the intersection of the instance of or office held field when we have an intersection with definition/identity predicate, and to keep the returned value as is in the other cases.