It is certain that Jessica is a mouse. Chances are slight that Sandra took the football. There is little chance that Julius is a rhino. It is improbable that if 'Sandra took the football and Julius is a rhino' then Yann is tired. It is unlikely that if 'Sandra took the football' or 'Jessica is a mouse' or both then Mary went to the office. It is highly likely that if 'Jessica is a mouse' or 'Julius is a rhino' or both then Bernhard is green.
There is little chance that 'Bernhard is green and Julius is a rhino'.
There is little chance that 'Bernhard is green and Julius is a rhino'.
It is almost certain that 'Bernhard is green and Julius 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
  1.0::factA.
  0.1::factB.
  0.1::factC.
  %hop1
  0.1::factX:-and(factB,factC).
  0.2::factY:-or(factB,factA).
  0.9::factZ:-or(factA,factC).

  %hop2
  conclusion:-and(factZ,factC).

  query(conclusion).
  
'Bernhard is green and Julius is a rhino'.