context: It is impossible that Julius is a frog. There is little chance that Brian is green. It is probably the case that Mary went to the office.
hypothesis: There is a better than even chance that 'Mary went to the office and Brian is green'.
valid_hypothesis: It is highly unlikely that 'Mary went to the office and Brian is green'.
invalid_hypothesis: There is a better than even chance that 'Mary went to the office and Brian is green'.
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
    0.0::factA.
    0.1::factB.
    0.7::factC.
    
  
    %hop2
    conclusion:-and(factC,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Mary went to the office and Brian is green'.