Autocatalytic Grammar

Autocatalytic Grammars

Rules generate new rules during derivation. The grammar evolves while you generate text.

Output

Tip: Generate completes a run; Step advances one derivation step (and may spawn new rules).

Live Grammar

Format: Nonterminal -> production | production. Terminals in quotes, nonterminals bare.

Advanced Settings

Seed (blank = random)

Max Steps per Run

Autocatalysis Rate

Termination Damping

Start Symbol

Catalyst Target Nonterminals (comma)

Starter Grammar (Editable)

# Initial seed: minimal - will grow itself. S -> A B A -> "hunger" | "faith" | "silence" | "salt" | "prayer" B -> C | D C -> "descends" | "circles" | "abides" D -> "loosens" | "burns" | "returns"

Lexicon

river, stone, ember, light, shadow, vow, grain, breath, ash, ladder, mirror, gate, thread, hunger, faith, silence, salt, prayer, dusk, tongue, sleep, thunder, root, wing, seed, wheel, debt, chain, desert, psalm

Runtime Stats

lexicon: 0 rules: 0 firings: 0 spawned: 0 mutations: 0

Autocatalytic Grammars - How it works

Mechanic: When a production fires during derivation, it can probabilistically synthesize a new production and graft it into the grammar immediately. That is the catalytic feedback loop.

• Firing: Rewrite the leftmost expandable nonterminal with one of its productions.
• Catalysis: With probability = Autocatalysis Rate, the fired rule spawns a new production into a target nonterminal.
• Synthesis: New productions mix existing symbols with lexicon words; terminals are quoted.
• Damping: Bias toward terminal-heavy productions increases with step count to ensure termination.
• Evolution: After 10+ firings the grammar drifts; compare Live Grammar before/after a run.

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