Chances are slight that Fred is in the cinema. There is a very good chance that Mary dropped the apple. It is probable that Julius is white. It is improbable that if either 'Julius is white' or 'Mary dropped the apple' but not both then Greg is gray. It is likely that if 'Julius is white and Fred is in the cinema' then John went to the garden. There is little chance that if 'Mary dropped the apple' or 'Julius is white' or both then Lily is green.
There is a very good chance that 'John went to the garden' or 'Mary dropped the apple' or both.
There is a very good chance that 'John went to the garden' or 'Mary dropped the apple' or both.
There is little chance that 'John went to the garden' or 'Mary 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.
  0.8::factB.
  0.7::factC.
  %hop1
  0.1::factX:-xor(factC,factB).
  0.7::factY:-and(factC,factA).
  0.1::factZ:-or(factB,factC).

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

  query(conclusion).
  
'John went to the garden' or 'Mary dropped the apple' or both.