Letters describing Sri Aurobindo's own spiritual experience and practice. Includes first-person accounts of inner states relevant to the vault's introspection parallel.
Key passage cited in this vault:
- "concretely the thought approaching" — Sri Aurobindo describes seeing a thought arriving as if to enter from outside, before it becomes surface mental activity. (Ch: "Nirvana and the Brahman") Cited in the concept-injection introspection finding as a structural parallel to a model detecting an injected activation before it influences output.