Short answers, pulled from the story.
Omnicide is the technical term for human extinction, referring to the hypothetical end of the human species. It can result from natural causes such as asteroid impact or large-scale volcanism, or from anthropogenic destruction, meaning self-extinction through human activity.
Estimates vary widely by source and risk type. The United Nations Office for Disaster Risk Reduction estimated in 2023 a 2-14% chance of an extinction-level event by 2100. Metaculus users as of May 2026 estimated a 2% probability of human extinction by that date. The Global Challenges Foundation placed annual extinction probability at a minimum of 0.05% per year.
On the 27th of December 2024, Geoffrey Hinton estimated a 10-20% probability of AI-caused extinction within the next 30 years. He also estimated a 50-100% probability of AI-caused extinction within the next 150 years.
The idea gained scientific acceptance during the Age of Enlightenment in the 17th and 18th centuries. By 1800, Georges Cuvier had identified 23 extinct prehistoric species. Charles Darwin's On the Origin of Species in 1859 treated extinction as a natural process and a core component of natural selection.
Parfit argued that the difference between killing 99% and 100% of humanity is greater than the difference between peace and killing 99%. Extinction eliminates not only living people but every potential future human, which he calculated represents an incomparably larger loss. He estimated the Earth will remain habitable for around a billion years, giving humanity enormous long-term potential.
In a 1945 essay, Russell wrote that "Mankind are faced with a clear-cut alternative: either we shall all perish, or we shall have to acquire some slight degree of common sense." He described the prospect for the human race as "sombre beyond all precedent."