Chances are slight that Mary picked up the milk. It is impossible that Bill went to the bedroom. There is almost no chance that Bernhard is a rhino. It is improbable that if 'Bernhard is a rhino' or 'Mary picked up the milk' or both then Greg is green. It is improbable that if 'Bill went to the bedroom and Bernhard is a rhino' then Julius is yellow. It is highly likely that if 'Mary picked up the milk and Bill went to the bedroom' then Jason is tired.
Chances are slight that 'Mary picked up the milk' or 'Julius is yellow' or both.
Chances are slight that 'Mary picked up the milk' or 'Julius is yellow' or both.
It is certain that 'Mary picked up the milk' or 'Julius is yellow' 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
  0.1::factA.
  0.0::factB.
  0.02::factC.
  %hop1
  0.1::factX:-or(factC,factA).
  0.1::factY:-and(factB,factC).
  0.9::factZ:-and(factA,factB).

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

  query(conclusion).
  
'Mary picked up the milk' or 'Julius is yellow' or both.