It is highly likely that Mary went to the bedroom. We doubt that Greg is a frog. There is little chance that Daniel dropped the apple. It is almost certain that if 'Daniel dropped the apple' or 'Mary went to the bedroom' or both then Julius is a rhino. It is unlikely that if 'Mary went to the bedroom' or 'Greg is a frog' or both then John put down the milk. It is certain that if 'Greg is a frog and Mary went to the bedroom' then Brian is white.
It is highly likely that 'Julius is a rhino' or 'John put down the milk' or both.
It is highly likely that 'Julius is a rhino' or 'John put down the milk' or both.
It is highly unlikely that 'Julius is a rhino' or 'John put down the milk' or both.

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

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

  query(conclusion).
  
'Julius is a rhino' or 'John put down the milk' or both.