A testimony to the tools that extend our humanity. We make the case that the lens is as foundational to the rise of the West as the printing press, by literally allowing people to see their work.

What happened when the first medieval scholar with failing eyesight was fitted with a pair of spectacles? This episode traces the history of vision correction from the reading stones of the 11th century to the laser surgeries of the 21st. It makes the argument that the mass production of eyeglasses effectively doubled the intellectual workforce by extending the productive life of scribes, scientists, and artisans. No glasses, no Galileo reading his own notes at 70; no Gutenberg proofing his press.