It was a slow day, and two of my friends and I had decided to go out for
some coffee at a local restaurant.  It was one of our favorite places
to eat, and it was conveniently located near campus.  My friends (we'll
call them "Bill" and "Mary") and I walked in at about 11:00 in the morning,
and sat down in one of the booths.  Our actions were eventually rewarded
by the appearance of our waitress, Sandy.  Sandy was a new hiree, and
had immediately won our displeasure the day she served our hot lunches
cold, and topped off the affiar by carrying my coffee with her thumb
wrapped over the rim of the cup.  Sandy was slow both in speed and in
thinking, and we groaned as we saw her approach our table.

This was going to be a long morning.

Or maybe not.  I turned to my friends an whispered, "Follow my lead..."

   "Are you ready to order?" she asked.

   "I'll order for us.  We'd like three coffees.  Two without decaf: one
   black with cream and one without anything; and one with decaf, without
   anything."

   She looked up, somewhat perplexed.  This was gonna be good-- I could tell.

   "So...that's three coffees...uh, one without decaf, one without decaf
   with cream, and one without anything."

   "...with decaf," added Mary.

   "I don't want any decaf in my coffee," Bill replied.

   Sandy scribbled on her order pad, then tried again.

   "Okay...so that's one coffee with decaf and cream, black.  One coffee
   without decaf ...  Wait.  Okay, that's three coffees, without decaf,
   one with cream, black; one without anything; and one with decaf."

   At this point, Mary interrupted.  "Don't listen to them.  They're just
   trying to confuse you.  We want three coffees.  One without decaf with
   cream; two with decaf:  one without cream and one with decaf."

   Sandy tore off the order slip and started over anew.

   "Okay...now wait a minute.  You want one without decaf, right?" she asked,
   pointing to me.

   "Yes.  But I want it black, with cream."

   She scribbled that down and then turned to Bill:  "What do you want in
   your coffee?"

   Bill replied, "I want one with decaf, but no cream."

   Mary interrupted, "But you just said a minute ago that you didn't want
   any decaf in your coffee!"

   "I changed my mind!"

   By this time, Sandy had had enough of this and looked up at us.  The
   expression on her face was a bizarre combination of confusion and
   cluelessness.

   "This doesn't make any sense..."

   Bill replied, "Okay...let's try again.  This time I'd like a Pepsi."

   Mary said, "I think I'll have a Pepsi, too.  But without Diet."

   The look of relief that had been on Sandy's face quickly washed away.

   "Can I have mine the same way, but with decaf?"