It is likely that Julius is gray. It is highly unlikely that Lily is a lion. It is highly likely that Brian is yellow. It is probable that if either 'Lily is a lion' or 'Brian is yellow' but not both then Greg is a swan. There is little chance that if 'Brian is yellow and Lily is a lion' then Sandra left the apple. There is almost no chance that if 'Brian is yellow and Lily is a lion' then Bill moved to the office.
It is highly unlikely that 'Lily is a lion and Julius is gray'.
It is highly unlikely that 'Lily is a lion and Julius is gray'.
It is certain that 'Lily is a lion and Julius is gray'.

  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
  0.7::factA.
  0.05::factB.
  0.9::factC.
  %hop1
  0.7::factX:-xor(factB,factC).
  0.1::factY:-and(factC,factB).
  0.02::factZ:-and(factC,factB).

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

  query(conclusion).
  
'Lily is a lion and Julius is gray'.