The high-def part of the eye is a very small part, relative to the total field of vision, but the eye is constantly moving around to keep it covering as much area as needed, depending on how wide an area you're focusing on. It's just like how there's a blind spot in the dead center of your field of vision, where there are no photoreceptive cells, but the same motion keeps you from "seeing" it. And the brain's visual processing puts all that together into a single, coherent, moving picture.

"Mathematics brought rigor to economics. Unfortunately, it also brought mortis."
- Kenneth Boulding