system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can a knife be sharp enough to cut to the touch or without even being felt?
gpt
Your skin is filled with nerves to detect damages. If a nerve cell is damaged it will tell the brain about it. But cells are actually bigger then people imagine. And sharp knifes have a very thin edge. Most microscopes can be used to see individual skin and nerve cells but even electromicroscopes might have issues seeing the edge of a sharp knife. So it is possible to use a knife to cut though the skin without hitting any nerves or to cut though the nerve without allowing it to fire a signal.