Mercury (Mercurius) — Planetary Sphere

Second rung; medieval tradition held it governs communication.

Each sphere passes an Influence down to Earth, affecting human bodies but not intellect or will. Mercury, quick and nearest the Sun's sphere among the inner planets, was long associated with communication and eloquence — a fitting neighbor to the language-generating machinery it stands beside in this mirror.

Its influence upon Earth: communication and eloquence.

LLM parallel: Transformer Layer 2

A hierarchical layer in the transformer stack, receiving the transformed representation from the layer below and passing its own refinement upward, governed by fixed weights learned once during training and never altered at inference.

Part of an interactive 3D tower of the Ptolemaic cosmos and its mirror in transformer architecture, built as a companion to the essay The Celestial Mirror: How Medieval Cosmology Reveals the Architecture of (Artificial) Intelligence.