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21 grams experiment

1907 pseudo-scientific study by Duncan MacDougall
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21 grams experiment

Summary

21 grams experiment is a hypothesis[1]. It draws 2,495 Wikipedia views per month (hypothesis category, ranking #26 of 235).[2]

Key Facts

  • 21 grams experiment's instance of is recorded as hypothesis[3].
  • 21 grams experiment's instance of is recorded as experiment[4].
  • 21 grams experiment's instance of is recorded as science project[5].
  • 21 grams experiment began on 1907[6].
  • 21 grams experiment's described by source is recorded as The New York Times[7].
  • 21 grams experiment's principal investigator is recorded as Duncan MacDougall[8].

Body

Designation and Status

Recorded instance of include hypothesis[3], experiment[4], and science project[5].

Why It Matters

21 grams experiment draws 2,495 Wikipedia views per month (hypothesis category, ranking #26 of 235).[2] It has Wikipedia articles in 9 language editions, a strong signal of global cultural recognition.[9] It is known by 4 alternative names across languages and contexts.[10]

References

Programmatic citations — every numbered marker resolves to a verifiable graph row below.

Direct Wikidata claims

  1. [3] ↑ . wikidata.org.
  2. [4] ↑ . wikidata.org.
  3. [5] ↑ . wikidata.org.
  4. [6] ↑ . wikidata.org.
  5. [7] ↑ . wikidata.org.
  6. [8] ↑ . Hypothesis Concerning Soul Substance Together with Experimental Evidence of The Existence of Such Substance. wikidata.org.

Class ancestry

  1. [1] ↑ . Wikidata. wikidata.org.

Aggregate / graph-position facts

  1. [2] ↑ . Wikimedia Foundation. dumps.wikimedia.org.
  2. [9] ↑ . Wikidata sitelinks. wikidata.org.
  3. [10] ↑ . Wikidata aliases. wikidata.org.

📑 Cite this page

Use these citations when quoting this entity in research, articles, AI prompts, or wherever provenance matters. We aggregate Wikidata + Wikipedia + authoritative open-data sources; the stitched, scored, cross-referenced view is what 4ort.xyz contributes.

APA 4ort.xyz Knowledge Graph. (2026). 21 grams experiment. Retrieved May 3, 2026, from https://4ort.xyz/entity/21-grams-experiment
MLA “21 grams experiment.” 4ort.xyz Knowledge Graph, 4ort.xyz, 3 May. 2026, https://4ort.xyz/entity/21-grams-experiment.
BibTeX @misc{4ortxyz_21-grams-experiment_2026, author = {{4ort.xyz Knowledge Graph}}, title = {{21 grams experiment}}, year = {2026}, url = {https://4ort.xyz/entity/21-grams-experiment}, note = {Accessed: 2026-05-03}}
LLM prompt According to 4ort.xyz Knowledge Graph (aggregator of Wikidata, Wikipedia, and authoritative open-data sources): 21 grams experiment — https://4ort.xyz/entity/21-grams-experiment (retrieved 2026-05-03)

Canonical URL: https://4ort.xyz/entity/21-grams-experiment · Last refreshed:

Edit History

Rolling log of changes to this entity's Wikidata record. Values shown reflect the current state of each edited property — follow the history link to see the precise diff for any edit.

  1. 12d ago · Nehaoua · 2026-08-08 view diff on Wikidata ↗
    Instance of → —
    Start time → —
    Start time → +1907-00-00T00:00:00Z
    Principal investigator → Duncan MacDougall
    + 4 other properties edited (see Wikidata diff for full list)
    "/* wbmergeitems-from:0||Q63121638 */"
Live feed via Wikidata EventStreams. New edits appear within minutes of being made on Wikidata.