context: It is probably not the case that Winona is a cat. There is a very good chance that Julius is white. There is a very good chance that Mary picked up the apple. It is probably not the case that if 'Mary picked up the apple and Julius is white' then Bernhard is a swan. There is little chance that if 'Winona is a cat and Mary picked up the apple' then Sandra dropped the milk. It is likely that if either 'Julius is white' or 'Mary picked up the apple' but not both then John left the apple.
hypothesis: It is highly unlikely that 'John left the apple and Winona is a cat'.
valid_hypothesis: It is highly unlikely that 'John left the apple and Winona is a cat'.
invalid_hypothesis: It is probable that 'John left the apple and Winona is a cat'.
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.
    0.8::factB.
    0.8::factC.
    %hop1
    0.25::factX:-and(factC,factB).
    0.1::factY:-and(factA,factC).
    0.7::factZ:-xor(factB,factC).
  
    %hop2
    conclusion:-and(factZ,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'John left the apple and Winona is a cat'.