Theory
rdfs:subPropertyOf is the property-level analogue of rdfs:subClassOf.
:childOf rdfs:subPropertyOf :relatedTo .
Now any :childOf triple entails a :relatedTo triple too.
What you actually get for free:
| You declare | You also assert | The reasoner infers |
|---|---|---|
:childOf rdfs:subPropertyOf :relatedTo | :Bob :childOf :Al | :Bob :relatedTo :Al |
:student rdfs:subPropertyOf :knows | :A :student :B | :A :knows :B |
:author rdfs:subPropertyOf :contributor | :X :author :Y | :X :contributor :Y |
Direction matters: the child triple entails the parent triple, never the other way around.