It Would Create a Paradox

"Good idea," Karyn answered. Jon held the stone. "I wish this stone never existed." They expected to see a flash of light emanate from the stone, but there was nothing. "What happened?" Karyn asked. Jon didn't know, so he made another wish to find out. Apparently, removing the stone from existence would negate all previous wishes, which the rules for using the stone forbid. "Isn't there something *else* we can do?" Karyn asked. "This thing is dangerous. We *have* to get rid of it."