There is a very good chance that Jason is tired. Chances are about even that Bernhard is a rhino. Chances are about even that Brian is a lion. There is a very good chance that if 'Bernhard is a rhino and Jason is tired' then Lily is white. It is probably the case that if either 'Bernhard is a rhino' or 'Brian is a lion' but not both then John got the milk. It is almost certain that if either 'Bernhard is a rhino' or 'Brian is a lion' but not both then Mary went to the office.
It is impossible that 'Brian is a lion' or 'Jason is tired' or both.
It is highly likely that 'Brian is a lion' or 'Jason is tired' or both.
It is impossible that 'Brian is a lion' or 'Jason is tired' 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
  0.8::factA.
  0.5::factB.
  0.5::factC.
  %hop1
  0.8::factX:-and(factB,factA).
  0.7::factY:-xor(factB,factC).
  0.95::factZ:-xor(factB,factC).

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

  query(conclusion).
  
'Brian is a lion' or 'Jason is tired' or both.