There is almost no chance that Winona is a mouse. It is impossible that Julius is a frog. There is almost no chance that John put down the milk. It is highly likely that if 'John put down the milk and Winona is a mouse' then Bill went to the bedroom. It is certain that if either 'Winona is a mouse' or 'Julius is a frog' but not both then Greg is a rhino. There is a better than even chance that if either 'John put down the milk' or 'Julius is a frog' but not both then Mary left the football.
There is a better than even chance that 'Julius is a frog and Greg is a rhino'.
It is impossible that 'Julius is a frog and Greg is a rhino'.
There is a better than even chance that 'Julius is a frog and Greg is a rhino'.

  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
  0.02::factA.
  0.0::factB.
  0.02::factC.
  %hop1
  0.9::factX:-and(factC,factA).
  1.0::factY:-xor(factA,factB).
  0.6::factZ:-xor(factC,factB).

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

  query(conclusion).
  
'Julius is a frog and Greg is a rhino'.