context: There is almost no chance that John picked up the apple. Chances are about even that Lily is a swan. It is almost certain that Bernhard is green. It is likely that if 'Bernhard is green' or 'Lily is a swan' or both then Winona is a wolf. We doubt that if either 'Bernhard is green' or 'Lily is a swan' but not both then Julius is yellow. It is probably not the case that if 'Lily is a swan and John picked up the apple' then Jeff left the football.
hypothesis: There is almost no chance that 'Winona is a wolf and John picked up the apple'.
valid_hypothesis: There is almost no chance that 'Winona is a wolf and John picked up the apple'.
invalid_hypothesis: It is probably the case that 'Winona is a wolf and John picked up 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
    0.02::factA.
    0.5::factB.
    0.95::factC.
    %hop1
    0.7::factX:-or(factC,factB).
    0.2::factY:-xor(factC,factB).
    0.25::factZ:-and(factB,factA).
  
    %hop2
    conclusion:-and(factX,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Winona is a wolf and John picked up the apple'.