{
  "id": "second-nature.native",
  "term": "second nature",
  "sense": "native",
  "pos": "noun",
  "status": "review",
  "level": 15,
  "domain": "psychology",
  "style": "folk",
  "definition": "a learned pattern whose running cost has fallen to zero, so the self-model can no longer tell it apart from what was never learned.",
  "folk_gloss": "something learned so well you do it without thinking",
  "emergence": {
    "components": [
      "learn.cognitive",
      "pattern.regularity",
      "repeats.action",
      "cost.economic",
      "self-model.reflexive",
      "read.information",
      "nothing.absence"
    ],
    "interaction": "Repetition drives a learned pattern's running cost toward nothing; when the cost reaches zero the self-model loses its only marker of learning, and files the pattern with what was always there.",
    "novel_properties": [
      "cost-erased learning",
      "unmarked acquisition",
      "indistinguishable from innate"
    ]
  },
  "examples": [
    {
      "text": "A driver of twenty years cannot narrate how to parallel park, and finds teaching it harder than doing it.",
      "domain": "everyday"
    },
    {
      "text": "A native speaker cannot state the grammar rule they never break.",
      "domain": "language"
    },
    {
      "text": "To a homing pigeon, the learned landmarks of its loft and its inherited sun compass are one route.",
      "domain": "biology"
    }
  ],
  "relations": [],
  "used_by": [],
  "forms": [
    "become second nature",
    "becomes second nature",
    "second nature"
  ],
  "closed": false,
  "provenance": {
    "author": "claude-opus-5:hand-curated",
    "date": "2026-08-22",
    "confidence": 0.8,
    "sources": [
      "folk phrase — the self-model drifting"
    ]
  },
  "canonical": "https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-second-nature.native"
}