It is improbable that Lily is white. There is a better than even chance that Mary put down the apple. It is unlikely that Julius is a lion. It is probably not the case that if 'Julius is a lion and Lily is white' then Sandra dropped the milk. There is a very good chance that if 'Mary put down the apple and Lily is white' then Emily is a mouse. There is almost no chance that if 'Mary put down the apple and Lily is white' then John went to the office.
There is a better than even chance that either 'John went to the office' or 'Mary put down the apple' but not both.
There is a better than even chance that either 'John went to the office' or 'Mary put down the apple' but not both.
It is highly unlikely that either 'John went to the office' or 'Mary put down the apple' but not 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.
  0.6::factB.
  0.2::factC.
  %hop1
  0.25::factX:-and(factC,factA).
  0.8::factY:-and(factB,factA).
  0.02::factZ:-and(factB,factA).

  %hop2
  conclusion:-xor(factZ,factB).

  query(conclusion).
  
Either 'John went to the office' or 'Mary put down the apple' but not both.