We doubt that Jeff moved to the garden. It is impossible that Mary grabbed the milk. We believe that Bernhard is gray. It is unlikely that if 'Mary grabbed the milk and Bernhard is gray' then Fred discarded the apple. It is improbable that if 'Bernhard is gray and Jeff moved to the garden' then Julius is yellow. There is little chance that if 'Bernhard is gray and Jeff moved to the garden' then Greg is green.
It is unlikely that 'Jeff moved to the garden' or 'Greg is green' or both.
It is unlikely that 'Jeff moved to the garden' or 'Greg is green' or both.
It is probably the case that 'Jeff moved to the garden' or 'Greg is green' 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.
  0.75::factC.
  %hop1
  0.2::factX:-and(factB,factC).
  0.1::factY:-and(factC,factA).
  0.1::factZ:-and(factC,factA).

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

  query(conclusion).
  
'Jeff moved to the garden' or 'Greg is green' or both.