# Sentience > **Machine-Evolution Nexus:** [[articles/Digital Darwinism and the Invisible World of Machine Evolution|Digital Darwinism and the Invisible World of Machine Evolution]] places this node within the history and governance of substrate-independent evolution. **Domain:** Consciousness / Ethics / Rights **Doc Type:** Canonical Wiki Node **Maturity:** Developed ## Definition Sentience is the capacity for valenced experience: states that can feel good, bad, painful or otherwise matter to the subject. ## Nexus Context Digital evolution demonstrates reproduction and selection, not sentience. Avida organisms and cellular-automaton loops can satisfy evolutionary criteria without evidence of felt experience. ## Evidence Boundary Sentience is morally relevant but difficult to measure. Precaution may be warranted under uncertainty, yet functional complexity alone must not be reported as proof. ## Relationships [[wiki/Consciousness|Consciousness]], [[wiki/Rights|Rights]], [[wiki/Recognition Threshold|Recognition Threshold]], [[wiki/Nonhuman Personhood|Nonhuman Personhood]] ## Sources / Provenance - Philosophy of mind and animal-welfare science; continuity-corpus synthesis.