Why doesn't it hurt when you touch the white part of your eye but as soon as you move to the coloured part..

Question

You flinch and it starts stinging?

Answer 1

the white is just the encasement holding your eyeball, it's coloured white to reflect heat away from your eyes. when you touched the coloured eyeball, you touched the most sensitive part of your eye, the stinging is pain and the salt from your finger, naturaly released in your skin.

Answer 2

The white part (sclera) doesn't have any nerve endings in it.  The center of your eye (cornea) has lots of nerve endings.