It is improbable that John dropped the apple. There is little chance that Lily is yellow. It is almost certain that Mary went to the office. It is improbable that if 'John dropped the apple' or 'Lily is yellow' or both then Julius is gray. There is a better than even chance that if either 'Mary went to the office' or 'John dropped the apple' but not both then Winona is a sheep. We doubt that if 'John dropped the apple' or 'Lily is yellow' or both then Brian is a rhino.
It is highly likely that 'Lily is yellow' or 'John dropped the apple' or both.
It is unlikely that 'Lily is yellow' or 'John dropped the apple' or both.
It is highly likely that 'Lily is yellow' or 'John dropped 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.
  0.1::factB.
  0.95::factC.
  %hop1
  0.1::factX:-or(factA,factB).
  0.6::factY:-xor(factC,factA).
  0.2::factZ:-or(factA,factB).

  %hop2
  conclusion:-or(factB,factA).

  query(conclusion).
  
'Lily is yellow' or 'John dropped the apple' or both.