system
Given the following post, respond as if you're commenting on Reddit:
human
Is the world outside our eyes blurry?

We have lenses that bend the light to our retina, but if those aren't set up properly everything is blurry. So if the lens is what makes us see sharply, does that mean the light on the outer side of the lens blurry? Does the real world look more like a gaussian blur in Photoshop?
gpt
Without a lens to focus light on a point or a cavity to limit light detection to a certain direction, a photosensitive cell would only be able to detect light intensity.  The world would appear essentially featureless, as photons from any object within the incident angle would all be detected at the same time.  If an object were extraordinarily close to the photodetector, so that it would block the vast majority of light from other objects, some blurry details could be made out.

If you take photosensitive cells and put them at the end of a cylinder, still without a lens, the world would indeed appear blurry, but featured.  Objects within the diameter of the cylinder would be detected by all the cells, while objects within a cone outside the cylinder's diameter would be detected by only some of the cells.

If a large field of photosensitive cells were behind an opaque membrane with a small opening, a fairly decent amount of detail could be discerned even without a lens.  Each cell would only detect light from a very specific angle, and though it would be a blurry image, it would likely be detailed enough to navigate and manipulate objects.  However, there's a tradeoff between the sharpness and intensity of the detected image, as narrowing the opening to increase sharpness would decrease total incident light, and vice versa.

Edit - forgot a word.