{
  "format_version": 3,
  "claim_natural": "Humans use only 10% of their brain at any one time.",
  "claim_formal": {
    "subject": "Human brain",
    "property": "proportion of brain actively used at any given time",
    "operator": ">=",
    "operator_note": "The claim asserts that only 10% of the brain is in use at any one time. This is disproved when >= 3 authoritative neuroscience sources reject the claim, providing evidence that substantially more than 10% of the brain is active at any given time. 'Use' is interpreted as neuronal activity detectable by functional brain imaging (fMRI, PET scans) or inferred from lesion studies.",
    "threshold": 3,
    "proof_direction": "disprove"
  },
  "evidence": {
    "B1": {
      "type": "empirical",
      "label": "Scientific American \u2014 neurologist Barry Gordon rejects the 10% myth",
      "sub_claim": null,
      "source": {
        "name": "Scientific American (Barry Gordon, Johns Hopkins)",
        "url": "https://www.scientificamerican.com/article/do-people-only-use-10-percent-of-their-brains/",
        "quote": "the \"10 percent myth\" is so wrong it is almost laughable, says neurologist Barry Gordon at Johns Hopkins School of Medicine in Baltimore"
      },
      "verification": {
        "status": "verified",
        "method": "full_quote",
        "coverage_pct": null,
        "fetch_mode": "live",
        "credibility": {
          "domain": "scientificamerican.com",
          "source_type": "major_news",
          "tier": 3,
          "flags": [],
          "note": "Major news organization"
        }
      },
      "extraction": {
        "value": "verified",
        "value_in_quote": true,
        "quote_snippet": "the \"10 percent myth\" is so wrong it is almost laughable, says neurologist Barry"
      }
    },
    "B2": {
      "type": "empirical",
      "label": "MIT McGovern Institute \u2014 the 10% claim is '100 percent a myth'",
      "sub_claim": null,
      "source": {
        "name": "MIT McGovern Institute for Brain Research",
        "url": "https://mcgovern.mit.edu/2024/01/26/do-we-use-only-10-percent-of-our-brain/",
        "quote": "the idea that we use 10 percent of our brain is 100 percent a myth"
      },
      "verification": {
        "status": "verified",
        "method": "full_quote",
        "coverage_pct": null,
        "fetch_mode": "live",
        "credibility": {
          "domain": "mit.edu",
          "source_type": "academic",
          "tier": 4,
          "flags": [],
          "note": "Academic domain (.edu)"
        }
      },
      "extraction": {
        "value": "verified",
        "value_in_quote": true,
        "quote_snippet": "the idea that we use 10 percent of our brain is 100 percent a myth"
      }
    },
    "B3": {
      "type": "empirical",
      "label": "University of Washington Neuroscience \u2014 no scientific evidence for 10% claim",
      "sub_claim": null,
      "source": {
        "name": "Neuroscience For Kids, University of Washington (Eric Chudler)",
        "url": "http://faculty.washington.edu/chudler/tenper.html",
        "quote": "There is no scientific evidence to suggest that we use only 10% of our brains"
      },
      "verification": {
        "status": "verified",
        "method": "full_quote",
        "coverage_pct": null,
        "fetch_mode": "live",
        "credibility": {
          "domain": "washington.edu",
          "source_type": "academic",
          "tier": 4,
          "flags": [],
          "note": "Academic domain (.edu)"
        }
      },
      "extraction": {
        "value": "verified",
        "value_in_quote": true,
        "quote_snippet": "There is no scientific evidence to suggest that we use only 10% of our brains"
      }
    },
    "A1": {
      "type": "computed",
      "label": "Verified rejection source count",
      "sub_claim": null,
      "method": "count(verified rejection citations) = 3",
      "result": "3",
      "depends_on": [
        "B1",
        "B2",
        "B3"
      ]
    }
  },
  "cross_checks": [
    {
      "description": "Multiple independent sources consulted",
      "fact_ids": [
        "B1",
        "B2",
        "B3"
      ],
      "agreement": true,
      "n_sources_consulted": 3,
      "n_sources_verified": 3,
      "sources": {
        "scientific_american": "verified",
        "mit_mcgovern": "verified",
        "uw_neuroscience": "verified"
      },
      "independence_note": "Sources are from different institutions: Scientific American (quoting Johns Hopkins neurologist), MIT McGovern Institute, and University of Washington. No organizational, funding, or ideological overlap.",
      "coi_flags": []
    }
  ],
  "adversarial_checks": [
    {
      "question": "Is there any peer-reviewed neuroscience study that supports the claim that only 10% of the brain is active at any given time?",
      "verification_performed": "Searched for: '10 percent brain myth credible support evidence true', '10% brain use scientific evidence peer-reviewed'. Reviewed results from Scientific American, Psychology Today, Wikipedia, Association for Psychological Science, MIT McGovern Institute, Medical News Today, and University of Washington.",
      "finding": "No peer-reviewed neuroscience study was found supporting the 10% claim. Every neuroscience source consulted explicitly labels it a myth. Brain imaging studies (fMRI, PET) consistently show activity throughout the entire brain, even during sleep.",
      "breaks_proof": false
    },
    {
      "question": "Could the 10% figure refer to the ratio of neurons to glial cells, making the claim technically true under a different interpretation?",
      "verification_performed": "Searched for: 'neurons 10 percent brain cells glial ratio'. Reviewed neuroscience sources on neuron-to-glia ratios.",
      "finding": "While roughly 10% of brain cells are neurons (the rest being glial cells), the claim says 'use only 10% of their brain,' which refers to brain regions being active, not cell-type ratios. Furthermore, glial cells are also functionally active \u2014 they support neuronal function, maintain homeostasis, and participate in signaling. The neuron/glia ratio does not support the claim as stated.",
      "breaks_proof": false
    },
    {
      "question": "Could William James's original 1907 statement be interpreted as literal neuroscience supporting the 10% claim?",
      "verification_performed": "Searched for: 'William James 1907 energies of men 10 percent origin'. Reviewed MIT McGovern and Wikipedia articles on the myth's origins.",
      "finding": "William James wrote in 'The Energies of Men' (1907) that 'we are making use of only a small part of our possible mental and physical resources.' He was speaking metaphorically about human potential, not making a neuroscientific claim about brain activity percentages. He never stated 10%, and his work predates functional brain imaging by decades.",
      "breaks_proof": false
    }
  ],
  "verdict": {
    "value": "DISPROVED",
    "qualified": false,
    "qualifier": null,
    "reason": null
  },
  "key_results": {
    "n_confirmed": 3,
    "threshold": 3,
    "operator": ">=",
    "claim_holds": true
  },
  "generator": {
    "name": "proof-engine",
    "version": "1.16.0",
    "repo": "https://github.com/yaniv-golan/proof-engine",
    "generated_at": "2026-04-16"
  },
  "proof_py_url": "/proofs/humans-use-only-10-of-their-brain-at-any-one-time/proof.py",
  "citation": {
    "doi": "10.5281/zenodo.19600322",
    "concept_doi": "10.5281/zenodo.19489851",
    "url": "https://proofengine.info/proofs/humans-use-only-10-of-their-brain-at-any-one-time/",
    "author": "Proof Engine",
    "cite_bib_url": "/proofs/humans-use-only-10-of-their-brain-at-any-one-time/cite.bib",
    "cite_ris_url": "/proofs/humans-use-only-10-of-their-brain-at-any-one-time/cite.ris"
  },
  "depends_on": []
}