We doubt that John left the milk. Chances are slight that Mary moved to the garden. It is highly likely that Jeff dropped the apple. It is probably the case that if 'John left the milk and Jeff dropped the apple' then Winona is a mouse. It is unlikely that if 'Jeff dropped the apple' or 'John left the milk' or both then Bill went to the office. It is unlikely that if 'Jeff dropped the apple' or 'Mary moved to the garden' or both then Brian is gray.
It is probable that 'John left the milk and Mary moved to the garden'.
There is almost no chance that 'John left the milk and Mary moved to the garden'.
It is probable that 'John left the milk and Mary moved to the garden'.

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

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

  query(conclusion).
  
'John left the milk and Mary moved to the garden'.