There is a very good chance that Bernhard is yellow. It is improbable that Jessica is a mouse. It is certain that Brian is a frog. It is certain that if 'Jessica is a mouse and Bernhard is yellow' then Jeff moved to the garden. It is probably not the case that if either 'Jessica is a mouse' or 'Brian is a frog' but not both then Greg is a lion. It is improbable that if 'Bernhard is yellow' or 'Brian is a frog' or both then Fred dropped the milk.
It is highly likely that 'Greg is a lion and Jessica is a mouse'.
It is impossible that 'Greg is a lion and Jessica is a mouse'.
It is highly likely that 'Greg is a lion and Jessica is a mouse'.

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

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

  query(conclusion).
  
'Greg is a lion and Jessica is a mouse'.