Exercise 4.65: Cy D. Fect, looking forward to
the day when he will rise in the organization, gives a query to find all the
wheels (using the wheel rule of 4.4.1):


(wheel ?who)

To his surprise, the system responds


;;; Query results:
(wheel (Warbucks Oliver))
(wheel (Bitdiddle Ben))
(wheel (Warbucks Oliver))
(wheel (Warbucks Oliver))
(wheel (Warbucks Oliver))

Why is Oliver Warbucks listed four times?