We live in a universe made up entirely of moving particles of matter, from rotating electrons to galaxies. We are not surprised when we see living things moving, but we would be surprised if we suddenly saw inanimate objects moving on their own. If the table in your living room was suddenly hovering in the air, or ping pong balls began circling each other, we would look for an explanation.
In our universe, matter is constantly moving. Not only do inanimate objects move, but they do so according to a fixed and precise regularity described in the equations of physics.
This phenomenon begs the question: how can inanimate objects move, and how is it possible that they all move precisely according to the same rules? If asked, most people would simply answer that the laws of nature drive matter in the universe. For example, apples fall from a tree because of the force of gravity. But this answer is not an adequate explanation. The laws of nature describe the way objects move, but not how.