We doubt that Lily is a rhino. It is impossible that Greg is green. It is unlikely that Julius is a frog. It is highly likely that if 'Greg is green and Lily is a rhino' then Yann is tired. Chances are slight that if either 'Greg is green' or 'Julius is a frog' but not both then John grabbed the apple. It is unlikely that if 'Lily is a rhino' or 'Julius is a frog' or both then Brian is a swan.
It is probable that 'Lily is a rhino' or 'Yann is tired' or both.
It is unlikely that 'Lily is a rhino' or 'Yann is tired' or both.
It is probable that 'Lily is a rhino' or 'Yann is tired' 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
  0.2::factA.
  0.0::factB.
  0.2::factC.
  %hop1
  0.9::factX:-and(factB,factA).
  0.1::factY:-xor(factB,factC).
  0.2::factZ:-or(factA,factC).

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

  query(conclusion).
  
'Lily is a rhino' or 'Yann is tired' or both.