context: Chances are about even that Julius is a rhino. There is little chance that Brian is white. It is certain that John moved to the garden. It is certain that if 'Brian is white and John moved to the garden' then Mary dropped the apple. It is improbable that if 'John moved to the garden and Brian is white' then Greg is yellow. We believe that if 'Julius is a rhino' or 'Brian is white' or both then Winona is a sheep.
hypothesis: Chances are about even that 'Julius is a rhino and John moved to the garden'.
valid_hypothesis: Chances are about even that 'Julius is a rhino and John moved to the garden'.
invalid_hypothesis: It is highly unlikely that 'Julius is a rhino and John 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
    0.5::factA.
    0.1::factB.
    1.0::factC.
    %hop1
    1.0::factX:-and(factB,factC).
    0.1::factY:-and(factC,factB).
    0.75::factZ:-or(factA,factB).
  
    %hop2
    conclusion:-and(factA,factC).
  
    query(conclusion).
    
hypothesis_assertion: 'Julius is a rhino and John moved to the garden'.