context: There is a better than even chance that Fred went to the office. It is unlikely that Brian is a rhino. There is a better than even chance that Sumit is hungry.
hypothesis: We believe that 'Brian is a rhino and Sumit is hungry'.
valid_hypothesis: It is improbable that 'Brian is a rhino and Sumit is hungry'.
invalid_hypothesis: We believe that 'Brian is a rhino and Sumit is hungry'.
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
    0.6::factA.
    0.2::factB.
    0.6::factC.
    
  
    %hop2
    conclusion:-and(factB,factC).
  
    query(conclusion).
    
hypothesis_assertion: 'Brian is a rhino and Sumit is hungry'.