system
Given the following post, respond as if you're commenting on Reddit:
human
Why can't we feel shapes?

If someone places a heart shaped metal, or to make things easier, a square shaped metal on my skin, I cannot really tell what form it is. Why? Does this depend on the size of the shape/the force being applied over the object meaning that the higher it is, the most likely I will recognize its shape? Thank you!

Edit: Not sure how I should categorize this post. If I've done it wrong let me know please.
gpt
You can feel shapes, in the areas of your skin where you have a high nerve density, for instance in your fingertips. It's easier to feel the shape of things if your fingertips are moving, but that's not totally necessary. 

Try it - take a coin out of your pocket, and place it on a tabletop. The front and back of the coin are easily identifiable, with a little practice.