"Hold up your hand and apparently see the grisly moving skeleton bones right through the skin and flesh! Try the same test with a dog or cats paw...."
"Gaze at an ordinary egg and you seem to see right through its shell! Is there a chick inside? Look at a pencil and apparently see the lead inside the very wood!"
"Now - if you have the nerve, look at a friends head and you'll swear you can see his own throbbing brain within his skull!"