It is highly likely that Bernhard is a rhino. It is probably not the case that Bill went to the office. There is little chance that Emily is a sheep. It is probably not the case that if 'Emily is a sheep and Bernhard is a rhino' then Daniel got the football. Chances are about even that if 'Bill went to the office and Bernhard is a rhino' then Mary moved to the garden. There is a very good chance that if either 'Bernhard is a rhino' or 'Bill went to the office' but not both then Greg is a swan.
It is highly likely that either 'Bernhard is a rhino' or 'Daniel got the football' but not both.
It is highly likely that either 'Bernhard is a rhino' or 'Daniel got the football' but not both.
We doubt that either 'Bernhard is a rhino' or 'Daniel got the football' but not 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
  0.9::factA.
  0.25::factB.
  0.1::factC.
  %hop1
  0.25::factX:-and(factC,factA).
  0.5::factY:-and(factB,factA).
  0.8::factZ:-xor(factA,factB).

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

  query(conclusion).
  
Either 'Bernhard is a rhino' or 'Daniel got the football' but not both.