It is probably not the case that Jason is tired. It is impossible that Sandra grabbed the milk. We believe that Mary went to the office. We doubt that if 'Sandra grabbed the milk' or 'Mary went to the office' or both then Jeff left the apple. There is little chance that if 'Jason is tired' or 'Sandra grabbed the milk' or both then John got the apple. There is almost no chance that if either 'Mary went to the office' or 'Sandra grabbed the milk' but not both then Julius is a frog.
It is impossible that 'John got the apple and Jeff left the apple'.
It is impossible that 'John got the apple and Jeff left the apple'.
It is certain that 'John got the apple and Jeff left the apple'.

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

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

  query(conclusion).
  
'John got the apple and Jeff left the apple'.