if something is required for something else then that something allows that something else
most_important_thing_have is each_other. another_way_to_say_separates_things is divides_objects. thing is substance. separated_thing is divided_thing. person is individual_unlike_other. else is river. thing is object. change is when_one_thing_becomes_another_thing. space is what_between_else. necessity is thing.