There is almost no chance that Mary grabbed the apple. There is a better than even chance that Julius is yellow. It is highly unlikely that Lily is a rhino. There is almost no chance that if 'Lily is a rhino and Mary grabbed the apple' then Brian is a lion. It is improbable that if either 'Mary grabbed the apple' or 'Julius is yellow' but not both then Greg is green. There is almost no chance that if 'Mary grabbed the apple and Julius is yellow' then Bernhard is gray.
Chances are about even that 'Julius is yellow and Greg is green'.
It is highly unlikely that 'Julius is yellow and Greg is green'.
Chances are about even that 'Julius is yellow and Greg is green'.

  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.
  0.6::factB.
  0.05::factC.
  %hop1
  0.02::factX:-and(factC,factA).
  0.1::factY:-xor(factA,factB).
  0.02::factZ:-and(factA,factB).

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

  query(conclusion).
  
'Julius is yellow and Greg is green'.