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Portrait of Peter Singer
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Peter Singer

Utilitarian of the expanding circle — animal liberation and effective altruism.

Utilitarianism21st CenturyAustralian1946 CE – present◦ Melbourne (Australia)20th century CE

Overview

One of the world's most influential living moral philosophers, Singer applies a rigorous utilitarian ethics to urgent practical questions. In Animal Liberation he argued that ignoring animal suffering is 'speciesism', a prejudice akin to racism. He contends that affluent people have a strong obligation to relieve extreme poverty, and helped inspire the 'effective altruism' movement. Provocative and consequential, he insists we take seriously the interests of all who can suffer.

What they supported — and why

Equal consideration of interests

SupportedThe interests of all beings capable of suffering deserve equal consideration; to discount an interest because of species is 'speciesism'.

WhyIf the capacity to suffer is what grounds moral status, then ignoring an animal's suffering simply because it is not human is an arbitrary prejudice, like racism or sexism.

The obligation to prevent suffering

SupportedIf we can prevent something very bad without sacrificing anything of comparable moral importance, we ought to do it — so the affluent must give substantially to relieve extreme poverty.

WhyDistance and numbers do not lessen a life's worth, so the same principle that makes us save a drowning child obliges us to help distant strangers in dire need.

Effective altruism

SupportedWe should use reason and evidence to do the most good possible with our resources.

WhyGood intentions are not enough; if the aim is to reduce suffering, we are obliged to direct help where it does the most good per unit of resource.

Causes championed

  • Reducing suffering, human and animal
  • Animal liberation
  • Effective altruism and global poverty relief

Issues wrestled with

  • Whose interests count morally?
  • What do the affluent owe the world's poor?
  • How should we do good?

Hurdles faced

  • Fierce controversy over his views on animals, disability, and end-of-life ethics
  • Protests that have at times shut down his lectures

Works & books

2 catalogued. Status shows how much survives to today.

Animal Liberation

Survives

c. 1975 CE

The founding text of the modern animal-rights movement.

Practical Ethics; The Life You Can Save

Survives

His applied ethics and his case for giving to relieve global poverty.

Read the texts free

Their works online — Open Library catalogues 0 works & editions.

Influenced by

Jeremy Bentham and MillR. M. HareHenry Sidgwick

Influenced

the animal-rights movementeffective altruismapplied and practical ethics

In their words

“If it is in our power to prevent something bad from happening, without sacrificing anything of comparable moral importance, we ought to do it.”

— Famine, Affluence, and Morality

Legacy

He made ethics practical and consequential, reshaping how millions think about animals, charity, and moral obligation.

Follow their questions

This thinker is a stop on these paths through philosophy.

Further reading

Cross-checked against these authoritative references.

Authority records

Linked into the wider knowledge graph via Wikidata — the stable spine other sources hang off.