context: We doubt that Daniel got the football. It is improbable that John left the apple. It is probable that Greg is gray. There is little chance that if 'Daniel got the football' or 'Greg is gray' or both then Lily is a rhino. It is impossible that if 'Greg is gray and Daniel got the football' then Mary went to the bedroom. It is impossible that if 'Daniel got the football and John left the apple' then Emily is a sheep.
hypothesis: There is almost no chance that 'Daniel got the football and John left the apple'.
valid_hypothesis: There is almost no chance that 'Daniel got the football and John left the apple'.
invalid_hypothesis: We believe that 'Daniel got the football and John left the apple'.
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.
    0.1::factB.
    0.7::factC.
    %hop1
    0.1::factX:-or(factA,factC).
    0.0::factY:-and(factC,factA).
    0.0::factZ:-and(factA,factB).
  
    %hop2
    conclusion:-and(factA,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Daniel got the football and John left the apple'.