context: It is certain that Sandra took the football. It is likely that Bernhard is yellow. There is a very good chance that Mary went to the garden. It is probably the case that if 'Mary went to the garden' or 'Bernhard is yellow' or both then Brian is a rhino. It is highly likely that if 'Bernhard is yellow' or 'Sandra took the football' or both then John picked up the apple. We doubt that if 'Sandra took the football and Mary went to the garden' then Lily is white.
hypothesis: Chances are slight that 'Lily is white and Brian is a rhino'.
valid_hypothesis: Chances are slight that 'Lily is white and Brian is a rhino'.
invalid_hypothesis: It is almost certain that 'Lily is white and Brian is a rhino'.
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
    1.0::factA.
    0.7::factB.
    0.8::factC.
    %hop1
    0.7::factX:-or(factC,factB).
    0.9::factY:-or(factB,factA).
    0.2::factZ:-and(factA,factC).
  
    %hop2
    conclusion:-and(factZ,factX).
  
    query(conclusion).
    
hypothesis_assertion: 'Lily is white and Brian is a rhino'.