context: It is almost certain that Julius is a rhino. It is highly unlikely that Mary grabbed the milk. There is a better than even chance that Lily is yellow. It is probably the case that if either 'Julius is a rhino' or 'Lily is yellow' but not both then Sandra took the football. It is highly unlikely that if 'Julius is a rhino and Mary grabbed the milk' then Bernhard is a swan. It is highly unlikely that if either 'Mary grabbed the milk' or 'Lily is yellow' but not both then John went to the garden.
hypothesis: It is impossible that 'Julius is a rhino and Bernhard is a swan'.
valid_hypothesis: It is impossible that 'Julius is a rhino and Bernhard is a swan'.
invalid_hypothesis: It is likely that 'Julius is a rhino and Bernhard is a swan'.
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.
    0.05::factB.
    0.6::factC.
    %hop1
    0.7::factX:-xor(factA,factC).
    0.05::factY:-and(factA,factB).
    0.05::factZ:-xor(factB,factC).
  
    %hop2
    conclusion:-and(factA,factY).
  
    query(conclusion).
    
hypothesis_assertion: 'Julius is a rhino and Bernhard is a swan'.