context: It is almost certain that Mary went to the hallway. It is probably the case that John discarded the apple. It is impossible that Julius is a frog. It is certain that if 'Mary went to the hallway' or 'John discarded the apple' or both then Emily is a sheep. It is unlikely that if either 'John discarded the apple' or 'Julius is a frog' but not both then Greg is gray. It is unlikely that if 'Mary went to the hallway' or 'Julius is a frog' or both then Brian is yellow.
hypothesis: It is certain that 'Emily is a sheep' or 'Brian is yellow' or both.
valid_hypothesis: It is certain that 'Emily is a sheep' or 'Brian is yellow' or both.
invalid_hypothesis: There is almost no chance that 'Emily is a sheep' or 'Brian is yellow' 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
    0.95::factA.
    0.7::factB.
    0.0::factC.
    %hop1
    1.0::factX:-or(factA,factB).
    0.2::factY:-xor(factB,factC).
    0.2::factZ:-or(factA,factC).
  
    %hop2
    conclusion:-or(factX,factZ).
  
    query(conclusion).
    
hypothesis_assertion: 'Emily is a sheep' or 'Brian is yellow' or both.