context: There is almost no chance that John left the milk. It is probably not the case that Lily is white. It is likely that Greg is a rhino. There is a better than even chance that if 'John left the milk and Greg is a rhino' then Antoine is thirsty. There is a very good chance that if either 'Greg is a rhino' or 'John left the milk' but not both then Jeff went to the bedroom. There is little chance that if either 'Greg is a rhino' or 'Lily is white' but not both then Brian is a swan.
hypothesis: There is a better than even chance that either 'Antoine is thirsty' or 'Jeff went to the bedroom' but not both.
valid_hypothesis: There is a better than even chance that either 'Antoine is thirsty' or 'Jeff went to the bedroom' but not both.
invalid_hypothesis: It is improbable that either 'Antoine is thirsty' or 'Jeff went to the bedroom' but not both.
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.
    0.25::factB.
    0.7::factC.
    %hop1
    0.6::factX:-and(factA,factC).
    0.8::factY:-xor(factC,factA).
    0.1::factZ:-xor(factC,factB).
  
    %hop2
    conclusion:-xor(factX,factY).
  
    query(conclusion).
    
hypothesis_assertion: Either 'Antoine is thirsty' or 'Jeff went to the bedroom' but not both.