There is a better than even chance that Jeff moved to the office. We doubt that John grabbed the apple. There is little chance that Bernhard is a frog. There is a very good chance that if 'Jeff moved to the office and Bernhard is a frog' then Brian is a rhino. We doubt that if 'Bernhard is a frog and John grabbed the apple' then Julius is a swan. It is probably the case that if 'Jeff moved to the office and John grabbed the apple' then Jessica is a mouse.
It is highly unlikely that 'Brian is a rhino and Jeff moved to the office'.
It is highly unlikely that 'Brian is a rhino and Jeff moved to the office'.
We believe that 'Brian is a rhino and Jeff moved to the office'.

  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
  0.6::factA.
  0.2::factB.
  0.1::factC.
  %hop1
  0.8::factX:-and(factA,factC).
  0.2::factY:-and(factC,factB).
  0.7::factZ:-and(factA,factB).

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

  query(conclusion).
  
'Brian is a rhino and Jeff moved to the office'.