Claim

Humans use only ten percent of their brains.

Type QUANTITATIVE · truth-evaluable: yes · status at snapshot: ACTIVE · created seq 148

Referenced 172 times: checked 0, looked up by assistants 0, viewed 121, shared 51. A count of attention, not evidence.

Topics

Neuroscience · d6193340 Statistics · d6193340

Assessment

Contradicted

Score: 0.0266 under ledger-default@0.3.0 at snapshot 27745

2 of 4 review checks done · 2 counted

2 independent evidence lineages · review checks 2 of 4 · stability HIGH

Main unresolved issue: 4 counted evidence items have no independence review; repeats of one origin may be counted as several coverage:dece0877-5ec5-8750-8a15-fa3954dadbf7

Not yet independently audited; some evidence was recorded by an anonymous contributor.

Why?

Strongest counted contradiction: The excerpt says humans use virtually every part of the brain and most of it is active almost all the time, contradicting the ten-percent claim. weight 1.800000 evidence

Suppressed as dependent: Neurologist Barry Gordon states that people use virtually every part of the brain and that most of it is active almost all the time.

Review gaps: independence reviewed, primary source reviewed

What would most change this: One independent, direct measurement that supports this claim would move it from Contradicted to Contradicted.

Hide calculation

0.0266 under ledger-default@0.3.0 at snapshot 27745 · state Contradicted · Review checks: 2 of 4 · stability HIGH · 4 sources, 2 independent lineages

Model ledger-default@0.3.0 (the default model, not the answer) · snapshot 27745 · trace sha256:82d946aed0d1d6907bcb2cf3f3866a376eee380f73a9406d1cd4b39e5c3c8a76

Last changed at entry seq 11057; nothing logged since has borne on this claim.

How the number was reached

Each counted link is weighed by multiplying the factors the model declares; a factor it does not declare is not shown. Every factor name below links to what that number means.

Link	Working	Weight	Counted as
dcf83eea contradict	relevance DIRECT 2.0 × observation DIRECT_TEXT 0.9 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	1.800000	1.800000
39c02e16 contradict	relevance DIRECT 2.0 × observation DIRECT_TEXT 0.9 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	1.800000	1.800000
36f25776 contradict	relevance STRONG 1.2 × observation EXPERT_ANALYSIS 0.3 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	0.360000	0.000000 (dependent strongest only, kept dcf83eea)
67ecf77c qualify	relevance MODERATE 0.6 × observation DIRECT_TEXT 0.9 × interpretation 1 step, 1 − 0.15 × 1 0.850000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	0.459000	0.000000 (non directional)

prior 0.50 → log-odds 0.000000 + -3.600000 (the counted weights) = -3.600000 → probability 0.0266

Under neighbouring settings of the same model: 0.0745 to 0.0092, a spread of 0.0653.

Half-even rounding, six places for weights and four for the probability. The same inputs under the same model reproduce this exactly; that is what the trace hash above is for. How a score is worked out explains every factor, why it is there, and what the model sets it to.

Your view

Registered views

Nobody has registered a view yet.

Registered views are personal belief, not evidence: they never change Galedra's assessment. Affiliations are self-declared and shown only for groups of 5 or more.

Checked as part of

Statements this claim was broken out of. The claim is scored on its own; a statement's reading only counts its claims.

“FACT CHECK YOUR TEACHERS 🧠 Humans only use 10% of their brains. Einstein failed math as a kid and still changed physics. The Great Wall of China is the only...” · 8 claims · 19 September 2026

Evidence for

None.

Evidence against

Neurologist Barry Gordon states that people use virtually every part of the brain and that most of it is active almost all the time.

From Do People Only Use 10 Percent of Their Brains? (Scientific American) Read 2026-09-18 Relevance STRONG Steps 0 Counted

An expert statement that the whole brain is used contradicts the ten percent figure.
Brain scans show that all brain areas are active regardless of activity.

From Ten percent of the brain myth (Wikipedia) Read 2026-09-18 Relevance DIRECT Steps 0 Counted
The excerpt says humans use virtually every part of the brain and most of it is active almost all the time, contradicting the ten-percent claim.

From Do People Only Use 10 Percent of Their Brains? (Scientific American) Read 2026-09-18 Relevance DIRECT Steps 0 Counted

Qualifications

At certain moments, such as resting and thinking, a person may be using only about ten percent of the brain.

From Do People Only Use 10 Percent of Their Brains? (Scientific American) Read 2026-09-18 Relevance MODERATE Steps 1 Counted

The only sense in which ten percent holds: momentary activity at rest, not capacity.

Suppressed as dependent

Evidence	Group	Kept instead
2fdf7206		dcf83eea

Inferences

Concluded from

None.

Used as a premise in

None.

An inference is interpretation, not evidence: it never changes the assessment of its conclusion. Each premise is a claim with its own evidence.

Threads

None. Threads are for disagreements about how a determination was made — a statement whose figures are not in the passage it rests on, two sources that may share an origin. Something about the world belongs in the evidence above.

Claim edges

None. Edges are stored and displayed; v0.1 does not propagate probability across them.

Review checklist

Review checks: 2 of 4

Check	Done	By
qualifiers reviewed	yes	99a61afd
opposing search done	yes	73d532f3
independence reviewed	no
primary source reviewed	no

Summary

Contradicted. The main contradiction is: The excerpt says humans use virtually every part of the brain and most of it is active almost all the time, contradicting the ten-percent claim. 5535d38c

1 further item repeats the same origin and is not independent evidence. 2fdf7206

Qualifier: At certain moments, such as resting and thinking, a person may be using only about ten percent of the brain. d880c2de

A search for evidence in the opposing direction found none. 73d532f3

Review checks: 2 of 4. coverage:dece0877-5ec5-8750-8a15-fa3954dadbf7

Generated by stub-v0.1; every sentence cites graph ids.

Contribution history

seq	event	detail
148	APPENDED
149	ACCEPT	AUTOMATIC_AFTER_VALIDATION
158	LINK_EVIDENCE	by eb3bac87 (accepted)
160	LINK_EVIDENCE	by eb3bac87 (accepted)
162	LINK_EVIDENCE	by eb3bac87 (accepted)
8366	TASK_RESULT	by 1efd24fe (accepted)

Score trace

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  "claim": "dece0877-5ec5-8750-8a15-fa3954dadbf7",
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      "group": null,
      "reason": "dependent_strongest_only",
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      "relevance": "STRONG",
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      "relevance": "MODERATE",
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      "effective_weight": "0.000000",
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  "model": "ledger-default@0.3.0",
  "prior": "0.50",
  "variants": {
    "spread": "0.0653",
    "permissive": "0.0092",
    "conservative": "0.0745"
  },
  "code_hash": "sha256:c61a6fdf35a754a0d7e958df149036a083c0eaeb7d2d2e52704ec32b0c36def7",
  "contested": false,
  "stability": "HIGH",
  "claim_type": "QUANTITATIVE",
  "config_hash": "sha256:86768038080b8ab5233f1e4b7aba10af05b5bb44caa432095150b90e81209809",
  "probability": "0.0266",
  "provisional": true,
  "evidence_sum": "-3.600000",
  "snapshot_seq": 11057,
  "prior_log_odds": "0.000000",
  "support_groups": 0,
  "model_dependent": false,
  "review_coverage": "0.50",
  "truth_evaluable": true,
  "assessment_state": "CONTRADICTED",
  "review_checklist": {
    "qualifiers_reviewed": {
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    "opposing_search_done": {
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  "contradict_groups": 2,
  "rounding_boundary": false,
  "posterior_log_odds": "-3.600000",
  "not_applicable_reason": null,
  "independence_unreviewed": 4
}