There is little chance that Mary grabbed the milk. We doubt that Antoine is thirsty. It is almost certain that John went to the kitchen. We doubt that if either 'Antoine is thirsty' or 'John went to the kitchen' but not both then Jeff moved to the office. It is improbable that if 'John went to the kitchen' or 'Mary grabbed the milk' or both then Brian is gray. It is improbable that if either 'John went to the kitchen' or 'Mary grabbed the milk' but not both then Daniel left the apple.
It is impossible that 'John went to the kitchen' or 'Daniel left the apple' or both.
It is almost certain that 'John went to the kitchen' or 'Daniel left the apple' or both.
It is impossible that 'John went to the kitchen' or 'Daniel left the apple' or both.

  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.
  0.2::factB.
  0.95::factC.
  %hop1
  0.2::factX:-xor(factB,factC).
  0.1::factY:-or(factC,factA).
  0.1::factZ:-xor(factC,factA).

  %hop2
  conclusion:-or(factC,factZ).

  query(conclusion).
  
'John went to the kitchen' or 'Daniel left the apple' or both.