It is improbable that Julius is green. We doubt that Emily is a cat. There is little chance that Brian is a rhino. There is a very good chance that if 'Julius is green' or 'Emily is a cat' or both then Bernhard is gray. Chances are about even that if either 'Emily is a cat' or 'Julius is green' but not both then Mary is in the hallway. It is probably not the case that if 'Emily is a cat and Brian is a rhino' then John took the milk.
It is likely that 'Emily is a cat and Mary is in the hallway'.
It is improbable that 'Emily is a cat and Mary is in the hallway'.
It is likely that 'Emily is a cat and Mary is in the hallway'.

  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.
  0.2::factB.
  0.1::factC.
  %hop1
  0.8::factX:-or(factA,factB).
  0.5::factY:-xor(factB,factA).
  0.25::factZ:-and(factB,factC).

  %hop2
  conclusion:-and(factB,factY).

  query(conclusion).
  
'Emily is a cat and Mary is in the hallway'.