context: There is a better than even chance that Lily is a frog. There is almost no chance that Gertrude is a sheep. It is probably not the case that Sandra dropped the milk.
hypothesis: It is impossible that 'Sandra dropped the milk and Gertrude is a sheep'.
valid_hypothesis: It is impossible that 'Sandra dropped the milk and Gertrude is a sheep'.
invalid_hypothesis: There is a better than even chance that 'Sandra dropped the milk and Gertrude is a sheep'.
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
    0.6::factA.
    0.02::factB.
    0.25::factC.
    
  
    %hop2
    conclusion:-and(factC,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Sandra dropped the milk and Gertrude is a sheep'.