It is highly unlikely that Sandra got the milk. It is probably the case that Lily is green. It is highly unlikely that Brian is yellow. It is probable that if 'Brian is yellow and Sandra got the milk' then Fred put down the apple. It is probably not the case that if either 'Brian is yellow' or 'Lily is green' but not both then John left the football. It is probably not the case that if either 'Brian is yellow' or 'Lily is green' but not both then Bernhard is a rhino.
There is a very good chance that 'Sandra got the milk and John left the football'.
It is impossible that 'Sandra got the milk and John left the football'.
There is a very good chance that 'Sandra got the milk and John left the football'.

  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
  0.05::factA.
  0.7::factB.
  0.05::factC.
  %hop1
  0.7::factX:-and(factC,factA).
  0.25::factY:-xor(factC,factB).
  0.25::factZ:-xor(factC,factB).

  %hop2
  conclusion:-and(factA,factY).

  query(conclusion).
  
'Sandra got the milk and John left the football'.