context: We doubt that John moved to the office. We believe that Emily is a mouse. Chances are slight that Bernhard is a frog. It is probably the case that if either 'John moved to the office' or 'Emily is a mouse' but not both then Sandra dropped the milk. It is probably not the case that if 'John moved to the office' or 'Emily is a mouse' or both then Brian is yellow. There is almost no chance that if either 'John moved to the office' or 'Emily is a mouse' but not both then Winona is a sheep.
hypothesis: It is probably not the case that either 'John moved to the office' or 'Bernhard is a frog' but not both.
valid_hypothesis: It is probably not the case that either 'John moved to the office' or 'Bernhard is a frog' but not both.
invalid_hypothesis: It is almost certain that either 'John moved to the office' or 'Bernhard is a frog' 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
    0.2::factA.
    0.75::factB.
    0.1::factC.
    %hop1
    0.7::factX:-xor(factA,factB).
    0.25::factY:-or(factA,factB).
    0.02::factZ:-xor(factA,factB).
  
    %hop2
    conclusion:-xor(factA,factC).
  
    query(conclusion).
    
hypothesis_assertion: Either 'John moved to the office' or 'Bernhard is a frog' but not both.