context: Chances are slight that Antoine is thirsty. It is probably not the case that Mary moved to the garden. We believe that Greg is a rhino. It is almost certain that if 'Greg is a rhino' or 'Antoine is thirsty' or both then Julius is green. We doubt that if 'Mary moved to the garden' or 'Greg is a rhino' or both then John left the apple. We doubt that if 'Mary moved to the garden' or 'Antoine is thirsty' or both then Brian is a swan.
hypothesis: It is probable that either 'Antoine is thirsty' or 'John left the apple' but not both.
valid_hypothesis: It is probably not the case that either 'Antoine is thirsty' or 'John left the apple' but not both.
invalid_hypothesis: It is probable that either 'Antoine is thirsty' or 'John left the apple' 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
    0.1::factA.
    0.25::factB.
    0.75::factC.
    %hop1
    0.95::factX:-or(factC,factA).
    0.2::factY:-or(factB,factC).
    0.2::factZ:-or(factB,factA).
  
    %hop2
    conclusion:-xor(factA,factY).
  
    query(conclusion).
    
hypothesis_assertion: Either 'Antoine is thirsty' or 'John left the apple' but not both.