It is probably the case that Julius is a rhino. We believe that Emily is a mouse. It is probably the case that Mary moved to the office. There is little chance that if either 'Mary moved to the office' or 'Emily is a mouse' but not both then Brian is a frog. Chances are about even that if either 'Mary moved to the office' or 'Julius is a rhino' but not both then Jeff went to the bedroom. It is certain that if either 'Julius is a rhino' or 'Emily is a mouse' but not both then Bernhard is a frog.
It is highly unlikely that 'Mary moved to the office and Emily is a mouse'.
Chances are about even that 'Mary moved to the office and Emily is a mouse'.
It is highly unlikely that 'Mary moved to the office and Emily 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
  0.7::factA.
  0.75::factB.
  0.7::factC.
  %hop1
  0.1::factX:-xor(factC,factB).
  0.5::factY:-xor(factC,factA).
  1.0::factZ:-xor(factA,factB).

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

  query(conclusion).
  
'Mary moved to the office and Emily is a mouse'.