context: It is probable that John went to the office. It is probably the case that Bernhard is gray. It is likely that Brian is a rhino. There is almost no chance that if 'Bernhard is gray and Brian is a rhino' then Lily is a lion. It is probably not the case that if 'Bernhard is gray' or 'Brian is a rhino' or both then Julius is yellow. It is almost certain that if 'Brian is a rhino and Bernhard is gray' then Daniel got the football.
hypothesis: Chances are about even that 'Brian is a rhino and John went to the office'.
valid_hypothesis: Chances are about even that 'Brian is a rhino and John went to the office'.
invalid_hypothesis: There is almost no chance that 'Brian is a rhino and John went to the office'.
problog: 
    and(A,B) :- A,B.
    or(A,B) :- A;B.
    nand(A,B) :- not(and(A,B)).
    nor(A,B) :- not(or(A,B)).
    xor(A,B) :- or(A,B), nand(A,B).
  
    %hop0
    0.7::factA.
    0.7::factB.
    0.7::factC.
    %hop1
    0.02::factX:-and(factB,factC).
    0.25::factY:-or(factB,factC).
    0.95::factZ:-and(factC,factB).
  
    %hop2
    conclusion:-and(factC,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Brian is a rhino and John went to the office'.