A radical new theory proposes that human consciousness does not depend on biological brains, suggesting that the "what it is like" aspect of existence could be realized by systems beyond flesh and blood. This "Copernican Principle of Consciousness," put forth by researchers Eric Schwitzgebel and Jeremy Pober, challenges the long-held assumption that consciousness is exclusive to specific biological structures.
This principle draws inspiration from the astronomical revolution led by Nicolaus Copernicus, who demonstrated that Earth is not the center of the universe. Schwitzgebel and Pober argue that humanity should not assume its own consciousness is special or unique without sufficient evidence. Instead, they advocate for the assumption that consciousness is not special until proven otherwise.
"The universe may contain minds stranger than we can imagine," said Professor Eric Schwitzgebel of the University of California. Consciousness is defined as the subjective experience of existence, differentiating beings like humans or octopuses from inanimate objects such as tables or cups. A key debate in science and philosophy revolves around whether consciousness is "substrate flexible," meaning it can be realized by various types of physical systems, analogous to how a cup can be made of glass or plastic.
Some theorists maintain that consciousness is not substrate-flexible, confining it to very specific biological systems. This perspective narrows the potential for conscious life to a small fraction of possibilities, particularly impacting the search for extraterrestrial life. If advanced civilizations are rare, and their biology vastly differs from Earth's due to diverse environments, they might be excluded from being considered conscious under the traditional view.
Dr. Jeremy Pober of the University of Lisbon elaborated that aliens could exhibit significant differences not only in their functional architecture but also in their fundamental biochemistry. Astrobiologists and biochemists have shown the plausibility of carbon-based life with biochemical compositions substantially different from humans. For instance, life evolving in Venus's sulfuric acid clouds might utilize silicon in a role analogous to sulfur in Earth's biochemistry.
However, Pober and Schwitzgebel contend that such biochemical differences do not preclude the possibility of consciousness. They propose that consciousness should not be presumed to require human-like biology, thus expanding the potential range of conscious entities in the universe. This could include hypothetical silicon-based life forms, though the researchers express skepticism about their biological viability.
The implications of this theory extend to artificial intelligence. While Pober remains hesitant about extending the flexibility of consciousness to silicon chips, Schwitzgebel suggests that abandoning the requirement of human biology makes it difficult to exclude silicon-based systems. He argues that philosophers have overemphasized the ability of silicon to replicate a human brain, rather than focusing on the broader question of what kinds of systems can be conscious.
"The spirit of the Copernican Principle is: we should believe that we as humans are special when we have evidence that says so, but not when we don't," Pober stated. He added that while humans have evidence of their superior intelligence on Earth, there is no reason to assume they are nearly the most intelligent species in the universe.