context: We doubt that Jessica is a mouse. Chances are about even that Greg is gray. We believe that Mary went to the garden.
hypothesis: It is impossible that 'Mary went to the garden and Greg is gray'.
valid_hypothesis: Chances are about even that 'Mary went to the garden and Greg is gray'.
invalid_hypothesis: It is impossible that 'Mary went to the garden and Greg is gray'.
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
    0.2::factA.
    0.5::factB.
    0.75::factC.
    
  
    %hop2
    conclusion:-and(factC,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Mary went to the garden and Greg is gray'.