Eric Schwitzgebel and Jeremy Pober say consciousness likely does not require flesh-and-blood biology, arguing in a new paper that it could arise in organisms built from radically different materials.
Their case rests on “substrate flexibility” — the idea that consciousness, like other functions, can be realized in multiple physical forms rather than one Earth-specific chemical recipe.
At least 1,000 behaviorally sophisticated extraterrestrial civilizations may have existed somewhere in the universe, they estimate, making it overly Earth-centric to assume only Earth-like organisms can be conscious.
The authors frame that view as a “Copernican principle of consciousness,” extending the idea that humans and Earth are not cosmically privileged to the question of which beings can have experience.
Current AI remains unresolved in their account: Pober doubts today’s hardware is conscious, while Schwitzgebel says rejecting biology as a requirement makes it harder to dismiss silicon systems outright.
As AI perfectly mimics human consciousness, how could we ever prove it isn't truly self-aware?
If consciousness isn't tied to biology, could intelligent life already be expanding across the cosmos undetected?
If alien minds are built from crystal and mercury, are we searching for intelligence in all the wrong places?
Consciousness Beyond Earth: Schwitzgebel and Pober’s Case for Substrate Flexibility and Cosmic Prevalence
Overview
Eric Schwitzgebel and Jeremy Pober argue that consciousness is not limited to Earth-like biology, but is likely widespread throughout the cosmos. Their central idea, substrate flexibility, suggests that consciousness can arise from many different physical materials, not just carbon-based life. This challenges traditional views and encourages a new way of searching for conscious experience beyond our planet. By proposing that consciousness could exist in forms very different from those we know, their work urges us to rethink our assumptions and expand our search for consciousness in the universe.