Chances are about even that Brian is yellow. We doubt that Sandra dropped the milk. It is impossible that Lily is a lion. It is almost certain that if 'Brian is yellow' or 'Sandra dropped the milk' or both then Mary went to the office. It is certain that if either 'Brian is yellow' or 'Sandra dropped the milk' but not both then John put down the milk. It is impossible that if either 'Brian is yellow' or 'Lily is a lion' but not both then Fred left the apple.
It is almost certain that 'John put down the milk and Brian is yellow'.
Chances are about even that 'John put down the milk and Brian is yellow'.
It is almost certain that 'John put down the milk and Brian is yellow'.

  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
  0.5::factA.
  0.2::factB.
  0.0::factC.
  %hop1
  0.95::factX:-or(factA,factB).
  1.0::factY:-xor(factA,factB).
  0.0::factZ:-xor(factA,factC).

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

  query(conclusion).
  
'John put down the milk and Brian is yellow'.