It is probable that Jeff went to the garden. It is likely that Sandra took the football. We believe that Mary left the milk. We doubt that if either 'Jeff went to the garden' or 'Sandra took the football' but not both then Julius is white. There is little chance that if 'Jeff went to the garden' or 'Mary left the milk' or both then Brian is a swan. It is unlikely that if either 'Sandra took the football' or 'Mary left the milk' but not both then Lily is a frog.
It is highly unlikely that 'Sandra took the football and Julius is white'.
It is highly unlikely that 'Sandra took the football and Julius is white'.
It is probable that 'Sandra took the football and Julius is white'.

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

  %hop2
  conclusion:-and(factB,factX).

  query(conclusion).
  
'Sandra took the football and Julius is white'.