@prefix : <https://eyereasoner.github.io/eye/reasoning#>.

{?p a :SymetricRelation. ?s ?p ?o} => {?o ?p ?s}.
{?p a :SymetricRelation. <<( ?s ?p ?o )>> ?p2 ?o2} => {<<( ?o ?p ?s )>> ?p2 ?o2}.
:marriedTo a :SymetricRelation.

:alice :marriedTo :bob.
<<( :alice :marriedTo :bob )>> :since "1999".

{:bob :marriedTo :alice} => {:TEST :PASS 1}.
{<<( :bob :marriedTo :alice )>> :since "1999"} => {:TEST :PASS 2}.
{<<( :alice ?p :bob )>> :since "1999"} => {:TEST :PASS 3}.
