context: It is impossible that Emily is a mouse. It is probable that Lily is a swan. It is unlikely that Greg is white. It is probably the case that if 'Emily is a mouse' or 'Greg is white' or both then John dropped the apple. It is unlikely that if 'Lily is a swan' or 'Emily is a mouse' or both then Brian is gray. We believe that if either 'Emily is a mouse' or 'Greg is white' but not both then Mary went to the bedroom.
hypothesis: It is probably the case that 'John dropped the apple' or 'Mary went to the bedroom' or both.
valid_hypothesis: It is unlikely that 'John dropped the apple' or 'Mary went to the bedroom' or both.
invalid_hypothesis: It is probably the case that 'John dropped the apple' or 'Mary went to the bedroom' or both.
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
    0.0::factA.
    0.7::factB.
    0.2::factC.
    %hop1
    0.7::factX:-or(factA,factC).
    0.2::factY:-or(factB,factA).
    0.75::factZ:-xor(factA,factC).
  
    %hop2
    conclusion:-or(factX,factZ).
  
    query(conclusion).
    
hypothesis_assertion: 'John dropped the apple' or 'Mary went to the bedroom' or both.