Cited by 1,864Psychology of Moral and Emotional JudgmentEthics and Social Impacts of AIEthics in Business and Education

The DOI matches its Crossref record; 33 of the 33 references it cites were found in a registry or an index; 3 of the 21 sources its claims cite were checked for support.

The Moral Machine experiment

Open access

Abstract

With the rapid development of artificial intelligence have come concerns about how machines will make moral decisions, and the major challenge of quantifying societal expectations about the ethical principles that should guide machine behaviour. To address this challenge, we deployed the Moral Machine, an online experimental platform designed to explore the moral dilemmas faced by autonomous vehicles. This platform gathered 40 million decisions in ten languages from millions of people in 233 countries and territories. Here we describe the results of this experiment. First, we summarize global moral preferences. Second, we document individual variations in preferences, based on respondents' demographics. Third, we report cross-cultural ethical variation, and uncover three major clusters of countries. Fourth, we show that these differences correlate with modern institutions and deep cultural traits. We discuss how these preferences can contribute to developing global, socially acceptable principles for machine ethics. All data used in this article are publicly available.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

The Moral Machine used a multilingual online game to gather millions of judgments about unavoidable autonomous-vehicle crash dilemmas, revealing strong global preferences for sparing humans, more lives, and younger lives. It also found demographic variation that did not reverse preferences, three broad cultural clusters, and country-level correlations with cultural and economic indicators.

Key findings

  • The platform collected 39.61 million decisions from 233 countries and territories; the abstract describes roughly 40 million decisions from over 2.3 million people in ten languages.
  • Worldwide, the strongest preferences were for sparing humans over animals, sparing more characters, and sparing younger characters; weaker preferences included sparing women and sparing pedestrians.
  • Among 492,921 respondents who completed the optional demographic survey, individual characteristics such as age, gender, income, education, politics, and religion did not change the direction of any preference, with effects all below 0.1.
  • Country-level clustering identified three groups—Western, Eastern, and Southern—and preferences correlated with individualism/collectivism, GDP per capita, rule of law, economic inequality, and gender gaps in health and survival.

Methods

  • The Moral Machine was an online “serious game” launched in June 2016 and later translated into nine additional languages; users chose between two outcomes in unavoidable accident scenarios.
  • In Judge mode, sessions contained 13 dilemmas generated around nine factors: species, number of lives, age, gender, physical fitness, social status, pedestrian legality, passenger versus pedestrian status, and whether the car swerves.
  • Analyses used conjoint analysis to estimate average marginal component effects, hierarchical clustering of 130 countries with at least 100 respondents, and country-level correlations with socio-economic and cultural indicators.

Limitations

  • The paper states that the sample was self-selected and not guaranteed to be representative, so policymakers should not treat the results as the final word on societal preferences.
  • The paper states that scenarios assumed certainty about character classification and life-and-death outcomes, did not manipulate respondent-character relationships, and captured preferences before autonomous vehicles are deployed.
  • Evident from the text: the findings are based on hypothetical choices from an internet-connected, tech-interested population, and the cross-sectional design cannot establish causal mechanisms behind country-level correlations.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1038/s41586-018-0637-6

Cites

33 of 33 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

38 Own result · 16 Own interpretation · 7 Own method · 7 No basis given · 6 No full text of the sources · 5 Sources not found · 3 Not checked yet · 2 Partly supported · 1 Supported · accuracy not yet measured

  • It may state two separate claims as one. 28
  • The quote only partly states this claim. 1
  • Probably not a substantial claim. 16
38 of 38
  • The paper relies on this without support.

    The 130 countries with at least 100 respondents are representative of their countries' moral preferences.

    “We selected the 130 countries with at least 100 respondents (N range = [101 -448,125])”
  • The paper relies on this without support.

    No research ever attempted to measure moral preferences using a 9-dimensional experimental design, in more than 200 countries.

    “No research ever attempted to measure moral preferences using a 9-dimensional experimental design, in more than 200 countries.”
  • The authors state this as an assumption.

    In the Moral Machine scenarios, characters were recognized as adults, children, etc. with 100% certainty, and life-and-death outcomes were predicted with 100% certainty.

    “In our scenarios, characters were recognized as adults, children, etc. with 100% certainty, and life-and-death outcomes were predicted with 100% certainty.”
    “These assumptions are technologically unrealistic, but they were necessary to keep the project tractable.”
  • The paper relies on this without support.

    The country from which users access the website, geo-localized through IP address, is a valid proxy for the country-level moral preferences of that country.

    “The country from which users access the website is geo-localized through the IP address of their computer or mobile device.This information is used to compute a vector of moral preferences for each country.”
4 of 4

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Citations

Cites

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Metadata

Authors
Awad, E., Dsouza, S., Kim, R., Schulz, J., Henrich, J., Shariff, A., Bonnefon, J.-F., & Rahwan, I.
Affiliations
  • MIT Media Lab (US)
  • Harvard University (US)
  • University of British Columbia (CA)
  • Centre National de la Recherche Scientifique (FR)
Corresponding author
  • Shariff, Azim
  • Bonnefon, Jean-François
  • Rahwan, Iyad
Venue
Nature
Published
2018-10-24
Volume
563
Issue
7729
Pages
59-64
ISSN
  • 0028-0836 (ISSN-L)
  • 1476-4687
OpenAlex
W2896252141
Cited by
1,859
References
31
Citations by year
2026: 214 · 2025: 263 · 2024: 222 · 2023: 270 · 2022: 273 · 2021: 263 · 2020: 223 · 2019: 120 · 2018: 10
FWCI
91.60
Type
journal article
Language
en
Open access
Locations
  • Nature (publishedVersion)
  • PubMed (publishedVersion)
  • Open Research Exeter (University of Exeter) (acceptedVersion)
  • DSpace@MIT (Massachusetts Institute of Technology) (submittedVersion)
  • RePEc: Research Papers in Economics (submittedVersion)
  • Figshare (submittedVersion)
  • MPG.PuRe (Max Planck Society) (submittedVersion)
Funders
Agence Nationale de la Recherche (ANR-17-EURE-0010, ANR-10-LABX-0029)
Topics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Psychology of Moral and Emotional Judgment
  • Physical Sciences › Computer Science › Artificial Intelligence › Ethics and Social Impacts of AI
  • Social Sciences › Business, Management and Accounting › Organizational Behavior and Human Resource Management › Ethics in Business and Education
Keywords
autonomous vehicles, machine ethics, ethical dilemmas, ethical preferences, cross-cultural variation, individual differences, demographic variation, modern institutions, cultural characteristics
MeSH terms
Accidents, Traffic, Pedestrians, Artificial Intelligence, Data Collection, Decision Making, Female, Humans, Male, Morals, Public Opinion, Robotics, Translating, Motor Vehicles, Internet, Internationality, Harm Reduction

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