The cornea is the storefront window of the optical economy. It charges no admission but extracts value through the simple act of permitting passage. Every photon that enters has already been taxed -- refracted, filtered, bent toward commerce. Transparency is never free. It is the most expensive surface in the body, maintained at the cost of 0.018 units per blink cycle, renewed every seven days without the owner's knowledge or consent.
The iris is the body's oldest authentication token. Long before fingerprints were rolled in ink, the iris was already performing identity verification -- each pattern as unique as a signature, as involuntary as a confession. The attention economy did not invent iris scanning. It merely noticed that the eye was already doing the work for free. Every glance is a biometric handshake. Every dilation is a signed contract.
The lens is the only organ that performs manual labor without a contract. It flexes and flattens thousands of times per day, adjusting focal length to serve whatever the attention economy places before it -- advertisements, notifications, terms of service no one reads. Accommodation is unpaid work. The lens does not choose what it focuses on. It merely bends. And like all laborers, it wears out: the presbyopic lens is a retired worker, stiff and clouded, still employed but no longer able to perform.
The retina is receipt paper. Every image that falls upon it is a transaction record -- an impression burned into photochemistry, filed without consent, stored in neural archives that the owner cannot access or delete. One hundred and twenty million rods, six million cones, each one a receipt printer. The retina does not photograph. It invoices. And the fovea, that exquisite pit of concentrated cones, is nothing more than a high-resolution scanner pointed permanently at whatever the attention economy has placed in the center of the visual field.
The optic nerve is a wire transfer -- one million axons bundled into a cable that carries the day's transactions from retina to cortex. It is the settlement layer of the visual economy, the channel through which every optical debt is cleared. The signal travels at 100 meters per second, a speed that would embarrass any modern payment network, and yet the nerve has been processing transactions without downtime for the entire duration of the organism's conscious existence. The blind spot where it exits the eye is the one receipt that was never printed.