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ResearchUC San Diego and Carnegie Mellon UniversityIn its training data

Rumelhart, Hinton & Williams popularize backpropagation

Confirmed

Importance: historic (5 of 5)

The takeaway

The Nature paper ‘Learning representations by back-propagating errors’ showed that multi-layer neural networks trained with backpropagation learn useful internal representations, reviving neural network research.

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Confirmed

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High confidence
Importance
Historic (5 of 5)
Last verified
29 September 2026

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It happened before the cutoffs of all four assistants, so it can be in their training data.

Key facts

  • Published in Nature vol. 323, 9 October 1986
  • Authors: David Rumelhart, Geoffrey Hinton, Ronald Williams
  • Showed hidden units learn features not present in inputs
  • Earlier related work includes Seppo Linnainmaa (1970) and Paul Werbos (1974)

What happened

The paper demonstrated gradient-based training of networks with hidden layers by propagating error derivatives backwards through the network.

Why it matters

Backpropagation is still how essentially all neural networks, including today’s LLMs, are trained.

Sources

2 sources from 2 sites. Numbers match the chips in the text.

2 sources: 1 primary, 1 reaction

Primary

  1. Learning representations by back-propagating errors (Nature, DOI)doi.org, paper

Reactions

  1. Wikipedia: Backpropagationen.wikipedia.org, discussion

Changes

  • Filed

Status

Claim

Confirmed

Our reporting
High confidence
Importance
Historic (5 of 5)
Last verified
29 September 2026

Sources at a glance

2 sources: 1 primary, 1 reaction

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
29 September 2026
Human review
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Version
Last saved 4 October 2026

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People in this story

Geoffrey Hinton, University Professor Emeritus, University of Toronto

The whole topic