(Eli5)Why is it that the sharper an object or blade gets the less pain you feel from it? Idk what flair I should put this as


Let’s say for example you have 3 objects
Broken piece of glass
That random kitchen knife that somehow is still able to cut
And a razor blade
I’ve been cut by all three of these objects in different places (except for the knife I’ve only cut my fingers on the knife)
And I’ve noticed that for the knife I felt the pain as soon as it started cutting
But with the razor blade and the piece of glass I didn’t even know I had gotten cut most of the time
And With the glass I didn’t get small nicks and cuts like I had somehow managed to get a 1” deep cut that ran all the way down the sole of my foot and didn’t notice until 1 I stepped into something that irritated the cut and 2 noticed that the ground felt slippery / wet

In: Biology

A sharper knife cuts more cleanly, causing less tearing of the skin compared to a dull or serrated knife. That tearing causes more nerve endings to be affected, and more pain to be felt.

Sharp objects slice cleanly through the nerve endings in your skin, while jagged objects rip and tear the skin and those nerve endings, resulting a much more intense pain sensation.

No expert here, but I think the finer the blade, or cutting surface, means you are doing less damage to the tissues around the wound.

The shape something is, the smaller the surface area at the cutting edge. The smaller the cutting edge, the smaller the amount of tissue gets torn up by the cutting edge. Think about inoculations. When you get a flu shot, it’s a pretty small needle going into the muscle. When you get penicillin (or one of its analogs) it’s a much bigger needle and the sensation increases significantly