context: It is highly unlikely that Mary went to the hallway. There is a very good chance that Julius is a frog. There is a better than even chance that Emily is a cat. It is probable that if 'Emily is a cat' or 'Julius is a frog' or both then Lily is yellow. It is unlikely that if 'Emily is a cat and Julius is a frog' then Bernhard is green. Chances are about even that if either 'Emily is a cat' or 'Mary went to the hallway' but not both then John picked up the apple.
hypothesis: It is probably the case that 'Mary went to the hallway' or 'Lily is yellow' or both.
valid_hypothesis: It is probably the case that 'Mary went to the hallway' or 'Lily is yellow' or both.
invalid_hypothesis: There is little chance that 'Mary went to the hallway' or 'Lily 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
    0.05::factA.
    0.8::factB.
    0.6::factC.
    %hop1
    0.7::factX:-or(factC,factB).
    0.2::factY:-and(factC,factB).
    0.5::factZ:-xor(factC,factA).
  
    %hop2
    conclusion:-or(factA,factX).
  
    query(conclusion).
    
hypothesis_assertion: 'Mary went to the hallway' or 'Lily is yellow' or both.