context: It is likely that Daniel took the milk. It is probably the case that Brian is green. It is certain that Bernhard is a swan. It is certain that if 'Brian is green and Bernhard is a swan' then Jessica is a mouse. It is probably the case that if 'Bernhard is a swan' or 'Brian is green' or both then Mary dropped the apple. It is probably not the case that if 'Bernhard is a swan and Brian is green' then Julius is a rhino.
hypothesis: It is improbable that 'Julius is a rhino and Mary dropped the apple'.
valid_hypothesis: It is improbable that 'Julius is a rhino and Mary dropped the apple'.
invalid_hypothesis: There is a very good chance that 'Julius is a rhino and Mary dropped the apple'.
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.
    0.7::factB.
    1.0::factC.
    %hop1
    1.0::factX:-and(factB,factC).
    0.7::factY:-or(factC,factB).
    0.25::factZ:-and(factC,factB).
  
    %hop2
    conclusion:-and(factZ,factY).
  
    query(conclusion).
    
hypothesis_assertion: 'Julius is a rhino and Mary dropped the apple'.