context: There is little chance that Fred discarded the apple. It is improbable that Lily is a lion. It is probably the case that Bernhard is gray. There is almost no chance that if 'Bernhard is gray' or 'Lily is a lion' or both then Brian is yellow. It is likely that if either 'Bernhard is gray' or 'Lily is a lion' but not both then John put down the milk. It is impossible that if either 'Lily is a lion' or 'Bernhard is gray' but not both then Mary moved to the garden.
hypothesis: It is impossible that 'Bernhard is gray and Mary moved to the garden'.
valid_hypothesis: It is impossible that 'Bernhard is gray and Mary moved to the garden'.
invalid_hypothesis: It is probable that 'Bernhard is gray and Mary moved to the garden'.
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
    0.1::factA.
    0.1::factB.
    0.7::factC.
    %hop1
    0.02::factX:-or(factC,factB).
    0.7::factY:-xor(factC,factB).
    0.0::factZ:-xor(factB,factC).
  
    %hop2
    conclusion:-and(factC,factZ).
  
    query(conclusion).
    
hypothesis_assertion: 'Bernhard is gray and Mary moved to the garden'.