context: It is certain that Bernhard is a swan. It is highly likely that Bill moved to the office. It is almost certain that Brian is yellow. There is a better than even chance that if 'Brian is yellow and Bernhard is a swan' then Daniel took the football. It is almost certain that if 'Brian is yellow and Bill moved to the office' then Mary dropped the milk. It is unlikely that if 'Brian is yellow' or 'Bill moved to the office' or both then John went to the bedroom.
hypothesis: It is highly unlikely that 'Brian is yellow and Bill moved to the office'.
valid_hypothesis: It is highly likely that 'Brian is yellow and Bill moved to the office'.
invalid_hypothesis: It is highly unlikely that 'Brian is yellow and Bill moved to the office'.
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
    1.0::factA.
    0.9::factB.
    0.95::factC.
    %hop1
    0.6::factX:-and(factC,factA).
    0.95::factY:-and(factC,factB).
    0.2::factZ:-or(factC,factB).
  
    %hop2
    conclusion:-and(factC,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Brian is yellow and Bill moved to the office'.