There is a very good chance that Winona is a mouse. It is almost certain that Brian is a frog. There is a very good chance that Sandra dropped the milk. Chances are about even that if 'Winona is a mouse' or 'Brian is a frog' or both then John got the apple. It is likely that if 'Sandra dropped the milk and Winona is a mouse' then Bernhard is green. It is impossible that if 'Brian is a frog' or 'Winona is a mouse' or both then Mary went to the bedroom.
Chances are about even that 'John got the apple and Sandra dropped the milk'.
Chances are about even that 'John got the apple and Sandra dropped the milk'.
It is certain that 'John got the apple and Sandra dropped the milk'.

  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
  0.8::factA.
  0.95::factB.
  0.8::factC.
  %hop1
  0.5::factX:-or(factA,factB).
  0.7::factY:-and(factC,factA).
  0.0::factZ:-or(factB,factA).

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

  query(conclusion).
  
'John got the apple and Sandra dropped the milk'.