It is highly likely that Brian is green. It is likely that Julius is gray. It is improbable that Emily is a wolf. It is impossible that if 'Brian is green' or 'Julius is gray' or both then Greg is a lion. Chances are slight that if 'Brian is green and Emily is a wolf' then John discarded the milk. It is unlikely that if 'Brian is green and Emily is a wolf' then Mary went to the garden.
There is almost no chance that 'Greg is a lion' or 'Mary went to the garden' or both.
There is almost no chance that 'Greg is a lion' or 'Mary went to the garden' or both.
It is likely that 'Greg is a lion' or 'Mary went to the garden' 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
  0.9::factA.
  0.7::factB.
  0.1::factC.
  %hop1
  0.0::factX:-or(factA,factB).
  0.1::factY:-and(factA,factC).
  0.2::factZ:-and(factA,factC).

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

  query(conclusion).
  
'Greg is a lion' or 'Mary went to the garden' or both.