context: It is probably not the case that John left the milk. Chances are about even that Mary went to the bedroom. There is a very good chance that Daniel took the football.
hypothesis: It is probably the case that 'John left the milk and Daniel took the football'.
valid_hypothesis: We doubt that 'John left the milk and Daniel took the football'.
invalid_hypothesis: It is probably the case that 'John left the milk and Daniel took the football'.
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
    0.25::factA.
    0.5::factB.
    0.8::factC.
    
  
    %hop2
    conclusion:-and(factA,factC).
  
    query(conclusion).
    
hypothesis_assertion: 'John left the milk and Daniel took the football'.