context: There is almost no chance that Fred left the football. There is a very good chance that Julius is yellow. It is unlikely that Greg is a lion. It is probable that if 'Julius is yellow' or 'Greg is a lion' or both then John moved to the garden. We doubt that if 'Julius is yellow and Greg is a lion' then Brian is gray. It is probably not the case that if 'Fred left the football' or 'Greg is a lion' or both then Mary went to the hallway.
hypothesis: There is a better than even chance that 'John moved to the garden and Julius is yellow'.
valid_hypothesis: There is a better than even chance that 'John moved to the garden and Julius is yellow'.
invalid_hypothesis: There is almost no chance that 'John moved to the garden and Julius is yellow'.
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.
    0.8::factB.
    0.2::factC.
    %hop1
    0.7::factX:-or(factB,factC).
    0.2::factY:-and(factB,factC).
    0.25::factZ:-or(factA,factC).
  
    %hop2
    conclusion:-and(factX,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'John moved to the garden and Julius is yellow'.