G.K. Chesterton devotes the first section of his treatise The Everlasting Man to what makes people special.
He begins with a simple image: cave paintings. Through images like the one below, he asks us to reimagine the caveman. Far from being a savage, the caveman was an artist.

Why does this matter? It’s telling that images like this one are what we have of our ancient ancestors. For all the speculation about how cavemen lived their lives, we only have their art.
It would be an odd thing if we found a horse’s artistic rendering of a person. Art is not only a sign of humanity. It’s a sign we are made in God’s image.
What’s true for painting is true for literature.