Essence of Knowledge

 is a Cypher of equipment in Torment: Tides of Numenera.

Description
This essence was put into a device to be placed over the eyes, where it injects a reddish-brown liquid into the retina. This gives one the ability to perceive the world with another, apparently more learned, perspective. Previously unknown knowledge of the Ninth World will be available to whoever consumes this essence. Unfortunately, the effect is merely temporary and leaves one with a rather persistent, and hard to scratch, itch on the corneas.

Location

 * Chiurgeon Slump: Sold by Sheen.