It is probably not the case that Jeff went to the bedroom. We believe that Julius is a swan. It is unlikely that Bernhard is a lion. It is likely that if either 'Julius is a swan' or 'Bernhard is a lion' but not both then Mary put down the apple. It is probably the case that if either 'Bernhard is a lion' or 'Jeff went to the bedroom' but not both then Sandra got the milk. It is likely that if 'Julius is a swan and Bernhard is a lion' then John left the football.
Chances are about even that 'Mary put down the apple and Julius is a swan'.
Chances are about even that 'Mary put down the apple and Julius is a swan'.
It is certain that 'Mary put down the apple and Julius is a swan'.

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

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

  query(conclusion).
  
'Mary put down the apple and Julius is a swan'.