Ars Arcanum

This chapter is an Ars Arcanum entry—an in-world scholarly reference guide. It provides systematic exposition on the magical systems of Roshar, including the Ten Essences, Ten Surges, fabrials (magical devices), Windrunner abilities (Lashings), Lightweaving, and Soulcasting, along with the author's theories about how these systems interrelate.

The chapter presents a comprehensive scholarly treatise on Roshar's magic systems. It begins with the Ten Essences and their symbolic associations with the Double Eye of the Almighty, noting uncertainty about how Voidbinding and the Old Magic fit into this framework. The Ten Surges are then detailed as the fundamental forces underlying Radiant abilities: Adhesion, Gravitation, Division, Abrasion, Progression, Illumination, Transformation, Transportation, Cohesion, and Tension. The text catalogs fabrials—mechanical magical devices powered by Stormlight and enslaved spren—organized into five groups: Augmenters (enhancing forces or sensations), Diminishers (opposite effect), Conjoiners (creating paired reactions across distance via rubies), Reversers (creating opposite reactions via amethysts), and Alerters (warning of nearby phenomena via heliodor). The chapter then explains Windrunner abilities, specifically the Three Lashings: the Basic Lashing (altering gravitational bonds), the Full Lashing (binding objects via Adhesion), and the Reverse Lashing (creating gravitational pull). Lightweaving is described as manipulating light and sound with a Spiritual component requiring mental imagery and Connection. Finally, Soulcasting is detailed as transforming matter via spiritual change, performed through Soulcaster devices requiring specific gemstones aligned to desired transformations, with the author noting this system's economy is based on transformation value rather than gemstone rarity. Throughout, the author theorizes about the cosmere-wide implications and connections between these systems.