In a conversation with the producers of “MONOLITH,” a planned documentary adaptation in tribute of Stanley Kubrick and Arthur C. Clark’s legendary film, 2001: A Space Odyssey, I suggested that perhaps extraterrestrials visited Earth a few million years and installed a monolith, metaphorically speaking. During that visit, some chimpanzees were endowed with consciousness and became the human species. “In that case,” I proposed, “the monolith is right in front of our eyes but we fail to recognize its extraterrestrial origin in the mirror.”
A few million years later, here we are as human capable of creating artificial intelligence (AI) out of silicon chips. But these AI systems consume gigawatts and require nuclear reactors to power them, whereas for a comparable performance the natural intelligence of the human brain consumes merely 20 watts, a hundred million times less power. In addition, biological brains are hosted by bodies that reproduce and are fueled by abundant materials from their environment. Silicon is abundant, but semiconductor chips are unable to reproduce by themselves. In fact, the manufacturing of silicon wafers for semiconductors requires meticulous design and extensive labor in a remote vacuum environment. This suggests that the biological infrastructure surrounding natural intelligence is far more efficient and sophisticated than current AI technologies. Once we figure how a human brain works, we might be able to power AI with car batteries instead of nuclear reactors. At that future time, we might also be able to endow brains of primitive animals with a higher level of intelligence and consciousness by a proper medical procedure. Accomplishing this feat will demonstrate the possibility that a similar operation might have been accomplished by interstellar visitors.
In this hypothetical scenario, the answer to Enrico Fermi’s question: “Where is everybody?” is: “Right here.” An interstellar gardener seeded Earth with advanced intelligence and consciousness and the evidence can be seen when we look at the mirror.” A groundbreaking paper in Nature magazine last month, reported that complete sequences of ape genomes show a 14% to 14.9% total genetic difference between humans and chimpanzees. One path to interstellar archaeology is to examine these differences and search for parts that could have been manipulated by interstellar visitors. The discoverers of such traces would resemble descendants of Genghis Khan recognizing that they share his genetic material.
Of course, the prevailing scientific view is that human intelligence evolved naturally within the confines of Earth without any interference of interstellar visitors. In that case, consciousness is an emergent phenomenon that resulted by chance and can be reproduced on exoplanets under similar circumstances, following the same organizing principles of biology.
Indeed, there are coincidences in nature that reflect an underlying principle. For example, the surface temperature of the Sun, 5,780 degrees Kelvin, is comparable to the temperature at which the cosmic microwave background was emitted, 3,000 degrees Kelvin, even though the density of the emitting gas is vastly different in the two cases. The reason for the similarity in emission temperature is that below that special temperature, free electrons are captured by protons to make hydrogen atoms, reducing dramatically the opacity of the gas to radiation and allowing us to see the radiation through transparent gas. The hydrogen fraction depends exponentially on temperature, making the emission temperature only logarithmically dependent on other parameters of the photosphere, such as the gas density.
If natural evolution is the key to human intelligence, a hint on what enabled humans to develop consciousness may be offered by AI systems. If AI will show similar cognitive qualities once the number of parameters in artificial neural network reaches the number of parameters in the natural neural network of the human brain, then we would know that consciousness emerges from a threshold level of complexity in any thinking entity.
In that case, consciousness might be superseded by higher cognitive states that are realized in neural networks with a larger number of free parameters than in the human brain. The complexity of the human brain was limited by its energy consumption, reaching about 20% of the metabolic load of the human body. But AI systems or alien intelligence may not respect the same limit. In that case, they could reach superhuman levels and represent the realization of Friedrich Nietzsche’s concept of “Übermensch,” which in traditional religions was taken by God.
Genesis 1:27 states: “So God created mankind in his own image.” The fundamental question is whether a superhuman intelligence from interstellar space created humans in its image or humans were created by natural evolution on Earth but will create a superhuman AI in their image. One way or another, humans will not be able to claim the top of the food chain for much longer. If superhuman alien intelligence exists, perhaps humans never were at the top of the interstellar food chain because most stars formed billions of years before the Sun. Acquiring this sense of humility will constitute the next Copernican revolution.
The film 2001: A Space Odyssey featured Johann Strauss II’s waltz “By the Beautiful Blue Danube,” as it showed a fictional spaceship docking with a space station on the background of the Earth and distant stars. On May 31, 2025, this musical piece will be broadcasted to the stars by a radio antenna in Spain operated by the European Space Agency (ESA), in celebration of the 50th anniversary of ESA’s creation, as well as 200 years since Strauss’ birth. There is no doubt that human intelligence is capable of magnificent accomplishments, but interstellar space may offer even more accomplished systems. We have the privilege of finding out as long as we do not surrender to the primitive focus of our ancestry on Earth.
ABOUT THE AUTHOR
Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.
