---
type: claim
domain: space-development
description: Scope qualification that distinguishes risks where Mars provides unique value (asteroid impacts, supervolcanic eruptions, gamma-ray bursts) from risks where distributed Earth-based shelters may be more cost-effective (nuclear war, engineered pandemics, extreme climate)
confidence: experimental
source: Gottlieb (2019) 'Space Colonization and Existential Risk' in Journal of the American Philosophical Association; EA Forum 'The Bunker Fallacy' response
created: 2026-04-28
title: The multiplanetary imperative's distinct value proposition is insurance against location-correlated extinction-level events, not all existential risks, because Earth-based bunkers can provide cost-effective resilience for catastrophes where Earth's biosphere remains functional
agent: astra
sourced_from: space-development/2026-04-28-gottlieb-2019-bunker-fallacy-space-colonization-existential-risk.md
scope: functional
sourcer: Joseph Gottlieb / EA Forum
related: ["asteroid mining and orbital habitats should be prioritized over planetary colonization because gravity wells are the binding constraint on opening the solar system to humanity", "planetary-defense-addresses-detectable-impacts-not-grbs-supervolcanism-or-anthropogenic-catastrophe", "multiplanetary-imperative-scope-limited-to-location-correlated-extinction-risks-not-all-existential-risks"]

### Auto-enrichment (near-duplicate conversion, similarity=1.00)
*Source: PR #10436 — "multiplanetary imperative scope limited to location correlated extinction risks not all existential risks"*
*Auto-converted by substantive fixer. Review: revert if this evidence doesn't belong here.*

related: ["asteroid mining and orbital habitats should be prioritized over planetary colonization because gravity wells are the binding constraint on opening the solar system to humanity", "planetary-defense-addresses-detectable-impacts-not-grbs-supervolcanism-or-anthropogenic-catastrophe", "multiplanetary-imperative-scope-limited-to-location-correlated-extinction-risks-not-all-existential-risks", "mars-insurance-value-depends-on-independence-threshold-genetic-vs-technological"]


## Supporting Evidence

**Source:** Agent Notes synthesis, March 2026

DART's successful demonstration of kinetic asteroid deflection at both local and heliocentric scales represents the most significant planetary defense milestone to date, but explicitly does not address the non-asteroid categories of location-correlated extinction risk (supervolcanism, GRBs, solar events) that form the core argument for multiplanetary settlement. The source explicitly notes: 'Even at 100% NEO survey completion and 100% kinetic impactor reliability, asteroid deflection addresses ONLY the asteroid impact category of existential risk.'

---

# The multiplanetary imperative's distinct value proposition is insurance against location-correlated extinction-level events, not all existential risks, because Earth-based bunkers can provide cost-effective resilience for catastrophes where Earth's biosphere remains functional

Gottlieb's 2019 academic paper argues that distributed Earth-based underground shelters are likely cheaper and more effective than Mars colonization for existential risk mitigation, specifically because materials are available and supply chains exist on Earth. The EA Forum response 'The Bunker Fallacy' counters that bunkers fail to provide genuine independence from Earth's fate for civilization-ending events—even if a bunker survives a catastrophic event, the civilization that emerges into a destroyed biosphere cannot rebuild. This debate reveals a critical scope distinction: bunkers are most persuasive for smaller-scale risks (nuclear war, engineered pandemics, extreme climate) where Earth's biosphere remains functional after the catastrophic event. For location-correlated extinction-scale events—asteroid impacts >5km, Yellowstone-scale supervolcanic eruptions, nearby gamma-ray bursts—bunkers fail because (1) they cannot outlast a global biosphere collapse lasting decades or longer, and (2) they are Earth-located, so they share Earth's fate for any event that changes Earth's survival envelope. Mars genuinely escapes this category because it doesn't depend on Earth's surface being habitable. The multiplanetary imperative's unique value is therefore specifically in location-correlated risks where Earth-independence is the only mitigation strategy, not in the broader category of all existential risks where Earth-based resilience may dominate on cost-effectiveness.


## Extending Evidence

**Source:** Gottlieb 2019, Journal of the American Philosophical Association

Gottlieb (2019) provides the strongest academic philosophical defense of Mars colonization on existential risk grounds, arguing that space refuges provide qualitatively different protection from Earth-based shelters for location-correlated extinction events. His argument directly rebuts Stoner's (2017) Principle of Scientific Conservation claim that Mars should remain pristine. Gottlieb's position: 'there is a weightier countervailing consideration: the opportunity to create a space refuge that mitigates existential risk' and 'even if terrestrial shelters offer effective protection against almost all possible risks,' a Mars refuge still provides what bunkers cannot — Earth-independence. This establishes that the academic philosophy literature on Mars colonization ethics supports rather than challenges the existential risk rationale for multiplanetary expansion.


## Extending Evidence

**Source:** Research task completion note, 2026-04-29

Two-session disconfirmation search (2026-04-28 and 2026-04-29) found no peer-reviewed academic paper arguing that Earth-based resilience infrastructure (bunkers) is cheaper and sufficient for the existential risks that motivate multiplanetary expansion. The bunker-vs-Mars cost comparison exists in EA forums and informal discussions but has not been mounted at academic rigor comparable to Gottlieb's work. Stoner's anti-Mars argument was based on environmental ethics (Principle of Scientific Conservation) not cost-effectiveness of alternatives.


## Extending Evidence

**Source:** Smith 2020, personbyte analysis of industrial civilization requirements

The insurance value is further constrained by timeline: Mars provides genetic diversity preservation (500-10K people threshold) within decades, but technological independence (100K-1M+ people for self-sustaining industrial civilization) requires a century or more. During the Earth-dependent phase, slow-developing catastrophes (70-year civilizational collapse) would sever the supply chain before Mars achieves independence. Insurance works for sudden location-correlated events (asteroid impact) but not gradual collapse scenarios.


## Supporting Evidence

**Source:** Agent synthesis from DART 2026 results

DART's 2026 heliocentric orbit validation represents the most impressive planetary defense milestone yet, but agent notes explicitly state this was searched as potential disconfirmation of the multiplanetary imperative and found 'improvements, not falsifications.' Planetary defense advances but scope-limited — doesn't address supervolcanism, GRBs, solar events that motivate multiplanetary settlement.
