How would you teach someone about human relationships like male female, intersex, father mother daughter son sibling wife husband grandfather grandmother uncle aunt etc and family trees and possibly how to research your own :-) the nature of relations ships like the brother of a brother or sibling is a brother (mathematical nature of relationships) half-siblings? how this can be vectorized? king - man + woman = queen ? etc :-) the notion of name and role in languages enabling explanation and reasoning in language :-) many ideas to be broken down into simpler ones :-)