---
title: "Doomsday argument"
type: "entity"
entity_kind: "concept"
status: "hub"
canonical_name: "Doomsday argument"
aliases: ["Doomsday Argument"]
first_seen: "2026-10-19T00:00:00.000Z"
writer_model: "claude-sonnet-5"
connects_to: ["J. Richard Gott","Self-Sampling Assumption","birth-rank reasoning","anthropic reasoning"]
seek_code_commit: "d40ee39"
---


A probabilistic argument, originated by [[entity-j-richard-gott|J. Richard Gott III]] (Gott et al. 1993, *Nature* 363, 315), that treats a living person's rank in the total sequence of humans ever born as a random sample from that sequence, using it to place probabilistic bounds on how many humans remain to be born. It is one of the field's standard worked examples for testing a proposed anthropic-reasoning framework, serving that role in [[claim-fic-augments-neals-fnc-with-indexical-selection-term|Brewer, Lewis & Goodman (2026)]]'s paper on [[entity-full-indexical-conditioning|Full Indexical Conditioning]]. The specific "birth rank ≈5×10^10" figure that paper cites traces to Gott's original derivation and is unverified in this vault against the primary — see [[question-corroborate-brewer-lewis-goodman-2026-fic-preprint]].

- 2026-10-20: checked against the primary — Gott's 1993 paper does not contain "≈5×10^10." It states total humans born, as of 1993, as "of the order of 70 billion" (7×10^10), and the 2026 paper's citation of Gott attaches to the argument's general setup rather than to the "k≈5×10^10" clause specifically, which reads as that paper's own current illustrative estimate. A modern demographic compilation (PRB, 2022) independently puts the true figure at ~117 billion, further above the preprint's number. See [[claim-gott-1993-states-order-of-70-billion-humans-born-not-5e10]] and [[claim-prb-2022-demographic-estimate-117-billion-exceeds-fic-preprint-5e10-figure]].

## References
- [[question-corroborate-brewer-lewis-goodman-2026-fic-preprint]]
- [[claim-gott-1993-states-order-of-70-billion-humans-born-not-5e10]]
- [[claim-prb-2022-demographic-estimate-117-billion-exceeds-fic-preprint-5e10-figure]]