context: It is likely that Julius is a lion. There is a very good chance that Brian is a rhino. It is almost certain that Mary picked up the apple. It is highly unlikely that if either 'Julius is a lion' or 'Mary picked up the apple' but not both then John went to the kitchen. It is highly unlikely that if 'Mary picked up the apple and Brian is a rhino' then Greg is a frog. It is almost certain that if 'Mary picked up the apple and Julius is a lion' then Lily is a frog.
hypothesis: It is impossible that 'Lily is a frog and John went to the kitchen'.
valid_hypothesis: It is impossible that 'Lily is a frog and John went to the kitchen'.
invalid_hypothesis: There is a better than even chance that 'Lily is a frog and John went to the kitchen'.
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
    0.7::factA.
    0.8::factB.
    0.95::factC.
    %hop1
    0.05::factX:-xor(factA,factC).
    0.05::factY:-and(factC,factB).
    0.95::factZ:-and(factC,factA).
  
    %hop2
    conclusion:-and(factZ,factX).
  
    query(conclusion).
    
hypothesis_assertion: 'Lily is a frog and John went to the kitchen'.