There is a better than even chance that Julius is white. There is a very good chance that Daniel dropped the apple. It is improbable that Mary moved to the garden. It is probable that if either 'Julius is white' or 'Daniel dropped the apple' but not both then Sandra left the milk. It is highly likely that if 'Julius is white and Mary moved to the garden' then Brian is a rhino. It is likely that if 'Daniel dropped the apple' or 'Mary moved to the garden' or both then Greg is a swan.
It is certain that 'Mary moved to the garden' or 'Sandra left the milk' or both.
Chances are about even that 'Mary moved to the garden' or 'Sandra left the milk' or both.
It is certain that 'Mary moved to the garden' or 'Sandra left the milk' 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
  0.6::factA.
  0.8::factB.
  0.1::factC.
  %hop1
  0.7::factX:-xor(factA,factB).
  0.9::factY:-and(factA,factC).
  0.7::factZ:-or(factB,factC).

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

  query(conclusion).
  
'Mary moved to the garden' or 'Sandra left the milk' or both.