It is probable that Bernhard is a frog. There is a very good chance that Daniel dropped the apple. It is probable that John moved to the office. It is likely that if 'Bernhard is a frog and Daniel dropped the apple' then Greg is yellow. It is probably the case that if 'Daniel dropped the apple' or 'John moved to the office' or both then Brian is yellow. It is almost certain that if 'John moved to the office' or 'Bernhard is a frog' or both then Jeff went to the garden.
Chances are about even that either 'Jeff went to the garden' or 'Greg is yellow' but not both.
Chances are about even that either 'Jeff went to the garden' or 'Greg is yellow' but not both.
It is almost certain that either 'Jeff went to the garden' or 'Greg is yellow' 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
  0.7::factA.
  0.8::factB.
  0.7::factC.
  %hop1
  0.7::factX:-and(factA,factB).
  0.7::factY:-or(factB,factC).
  0.95::factZ:-or(factC,factA).

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

  query(conclusion).
  
Either 'Jeff went to the garden' or 'Greg is yellow' but not both.