;;; THE INTRO TO AI SHOW
;;; Summer Session I 1999
;;;
;;; DEMO:
;;; "Ralph on net worth of Bringsjord brothers"
;;;
;;; by Selmer Bringsjord


;;; Set up the two competing Bringsjord brothers
;;; as special variables.

(defvar *Conrad*)
(defvar *Selmer*)

;;; Scripted questions for Ralph to pull in info for computing
;;; net worth of Bringsjord brothers.  An error in processing
;;; occurs if Selmer is honest on the first pass about his age.
;;; How would you fix that?

(defun ralph ()
	"Ralph's insulting interrogation about net worth."
	(format t "~%Hello O Most Sorry Excuse for a Vulcan...")
	(format t "~%You are a professor.  What profession is your brother?~%")
	(setf *Conrad* (list (read)))
	(format t "~%I see; impressive.  And what is Conrad's age?~%")
	(setf *Conrad* (cons (read) *Conrad*))
	(format t "~%Very well.  And what about your own age?~%")
	(setf *Selmer* (list (read) 'professor))
	(if (< (first *Selmer*) 35) (format t "~%Yeah, right.  Try again:"))
	(setf *Selmer* (list (read) 'professor))
	(format t "~%Hmm.  Either you are still lying -- or you aren't aging well at all.")
	(format t "~%I heartily recommend a synthetic body.")
	(format t "~%At any rate, I offer you now a function to compute net worth."))

(defun net-worth (person)
	"Computes the net worth of a person based on that person's profession."
	(cond ((eql 'investment-banker (second person)) (* (first person) 100000))
		((eql 'professor (second person)) (* (first person) 10))
		((eql 'student (second person)) (* (first person) 100))
		( t '(The profession of the person you have entered is unknown to me))))