(Britannica, 2025)
You can also download and read or share a .pdf of the complete text of this essay by scrolling down to the bottom of this post and clicking on the Download tab.
Everybody is Already Here: A Neo-Kantian Solution to the Fermi Paradox
According to a weak version of Immanuel Kant’s doctrine of transcendental idealism as it’s formulated in the Critique of Pure Reason (Kant, 1781/1787/1997), necessarily, the essential structures of the manifestly real natural universe or cosmos conform to the innately specified structures of our rational human capacities for cognition, caring, and action (Hanna, 2015: esp. section 7.3). This explains skepticism-proof rational human empirical and a priori knowledge. Moreover, if weak transcendental idealism is true, then this means that nothing in the cosmos is so alien that rational human animals cannot recognize, understand, and know it, at least to some salient degree, within the natural limits of our finitude, fallibility, and thoroughgoing normative imperfection.
The Fermi Paradox, formulated by the physicist Enrico Fermi as an open question—“where is everybody?”—says that it’s a cosmic mystery that we possess no evidence of intelligent extraterrestrial life, despite the manifestly real natural universe’s massive scale (see, e.g., Ball, 1973; Hanson, 1998; Ward and Brownlee, 2000; Webb, 2002; Kurzweil, 2005; Bostrum, 2008; Jasty, 2014; Worden et al., 2017; Sandberg et al., 2018; Loeb, 2021; Britannica, 2025; SETI Institute, 2025).
Here are six possible solutions to the paradox:
1. The Zoo Hypothesis
Like the Federation in Star Trek, super-intelligent alien life may answer to a Prime Directive: don’t interfere. Also known as the Zoo Hypothesis, this theory was formally proposed as a solution to the Fermi Paradox by John Ball at the Harvard-Smithsonian Center for Astrophysics in 1973.
https://www.youtube.com/watch?v=vux3qRTkJLo
Given the age of the universe, Ball noted, multiple type III civilizations may have appeared millions or even billions of years before intelligent life developed on Earth. With such a vast head start, these first civilizations would have complete control over the universe. They’d be able to destroy or control less advanced forms of life, like humans have done on Earth. They would have to grapple with the same ethical question as the Federation in Star Trek: what’s the right way to interact with less advanced civilizations, some millions of years behind?
On Earth, we’ve decided to create nature reserves and national parks, places where generations of ants may never come in contact with a human. Likewise, entire alien civilizations may have agreed to let us be, to let us mature and evolve naturally, to observe our progress from afar, hiding from us until they decide we’re ready to join the extraterrestrial community.
2. We’re living in a simulated universe
Call them crazy, but renowned scientists and philosophers are developing increasingly creative (some would say delusional) ideas about how a simulated universe would work. Some of their arguments are logical, perhaps even convincing, and they’ve been debated by serious academics in serious journals for years now.
Nick Bostrom, a philosopher at Oxford and director of the Future of Humanity Institute, has developed my favorite argument in a paper called, “Are You Living in a Computer Simulation?” He argues that at least one of the following three statements must be true:
1. Humans are likely to go to extinct before they are “posthuman” and able to create entirely simulated realities (i.e. an entirely simulated universe).
2. A post-human civilization with the ability to run such a simulation would likely not run many simulations (because of the immense amount of resources needed, perhaps, or the ethical considerations of the beings in the simulation).
3. We are currently living in a computer simulation.
Using extremely clever logic and a bit of mathematical fiddling, Bostrom concludes that “the belief that there is a significant chance that we will one day become post-humans who run ancestor-simulations is false, unless we are currently living in a simulation.” Remember, this is a philosopher at Oxford speaking.
https://www.youtube.com/watch?v=nnl6nY8YKHs
How would such a simulation be created? Writers have long speculated that a Type II or III civilization might develop a “Matrioshka brain,” an almost inconceivably huge computer system that runs on the entire energy output of a star. Using a Dyson sphere, a shell around a star that captures all the energy of the star, mathematicians have calculated that a Matrioshka brain could have the computational power to create a simulated universe, with all of us living inside. This idea, believe it or not, doesn’t appear to violate any laws of physics we know about.
3. Aliens are broadcasting, but we don’t know how to listen
SETI (the search for extraterrestrial intelligence) is counting on this solution. With a little imagination, it’s easy to think of a number of reasons why we haven’t been able to communicate with aliens.
Aliens might not be broadcasting with radio waves, or they might be broadcasting on different frequencies than the ones SETI is currently monitoring. They might use neutrinos or lasers to communicate across the galaxy in a kind of “galactic” internet. Complex compression algorithms that we don’t understand, gamma ray bursts that we can’t detect, modulation methods that we haven’t discovered — the list goes on and on.
In 1985, Carl Sagan came up with an especially compelling reason for why we’re missing alien signals. He speculated that aliens may communicating at a rate so slow or fast that we don’t even recognize their efforts. If an alien civilization takes years to broadcast a single sentence, or even a single word, we not even recognize that we’re being contacted.
They may be communicating with Matrioshka brains, or even more advanced technologies that we can’t imagine and may never discover. Humans have been searching for signals from extraterrestrial life for less than 100 years, using techniques that aliens may have abandoned millions of years ago, or perhaps skipped all together. The chance that our method of communication aligns perfectly with an alien civilization’s method begins to look slim indeed.
4. The “Rare Earth” hypothesis
The Rare Earth hypothesis disputes the first and second assumptions of the Fermi paradox, which suppose that the Earth is a typical planet revolving around a typical star. There’s something special, or at least rare, about Earth, proponents of the Rare Earth hypothesis claim, that allowed complex to form and thrive on its surface.
In 1961, Frank Drake, an American astronomer, created a simple equation to estimate the number of intelligent civilizations in our galaxy. Using rough approximations, Drake calculated that there were at least 1000 and perhaps as many as 100 million extraterrestrial civilizations in the Milky Way alone, but these numbers are highly disputed. Although recent NASA missions have found hundreds of exoplanets, or Earth-like planets, revolving around stars in the Milky Way, scientists still don’t know how life originates on a planet….
Perhaps life needs a planetary solar system with gas giants far from the sun and rocky planets closer in. Maybe plate tectonics and volcanoes are necessary to create suitable atmosphere for life. Evolving life may need a large moon that cause tides, a specific temperature or a planet with a stable orbit. With a sample size of 1 (the only thing we know for sure is that life developed on Earth), it’s nearly impossible to determine whether or not life is rare in the universe.
5. The Youngness Paradox
Alan Guth, theoretical physicist at MIT and likely contender for this year’s Nobel Prize, developed his own solution for the Fermi Paradox that stands above the rest in its sheer astounding-ness, and we’re talking about a field replete with astounding ideas.
In a paper called “Eternal Inflation and its Implications,” Guth used the physics of inflation to elegantly show that each universe (by the way, we’re assuming the existence of an infinite number of universes) likely has only one advanced civilization.
Here’s how the argument goes: according to Guth, cosmic inflation spawns an infinite number of pocket universes at an extraordinary rate. In fact, every second number of pocket universes increases by a factor of 10^37. Therefore, Guth argues, we can assume that young pocket universes vastly outnumber older universes. In other words, the average universe is remarkably young.
Guth then postulates that there is a minimum time—let’s call it T—required for intelligent life like ours to develop. Because we’ve already developed, we know that the age of our universe is greater than or equal to T.
Let’s imagine there is another civilization in our universe more advanced then ours, and for the sake of argument, let’s assume that it is one second more advanced. If the minimum time for our civilization to develop is T, the minimum time for this more advanced civilization to develop is greater than or equal to T + 1s.
Because the number of universes that satisfy the T requirement is 10^37 times the number of universes that satisfy the T + 1s requirement, and because we know only that we live in a universe that satisfies the T requirement, it is extremely unlikely that our universe also satisfies the T+1s requirement. It’s unlikely, therefore, that there is an alien civilization in our own universe even one second more advanced than ours.
https://www.youtube.com/watch?v=Fto2HTtnz6g
6. The Great Filter
The Great Filter is the idea that the development of a civilization that can colonize a galaxy is a unique, maybe once in a universe event because of the many exceptional barriers to life along the way. Dr. Robin Hanson, a well known futurist at George Mason University and the Future of Humanity Institute, published the nine steps he believes are required to get from a suitable planet to an interstellar civilization:
1. The right star system (including organics)
2. Reproductive something (e.g. RNA)
3. Simple (prokaryotic) single-cell life
4. Complex (archaeatic & eukaryotic) single-cell life
5. Sexual reproduction
6. Multi-cell life
7. Tool-using animals with big brains
8. Where we are now
9. Colonization explosion
These nine steps to a colonization explosion are the “Great Filter.” Proponents of the Great Filter argue that the transition between one or more “filtering” step (and of course there may be many more steps we don’t know about) may be so uncommon that few civilizations reach step 8 or 9. If each transition is sufficiently uncommon, humans may be the only life-form in the galaxy that ever reaches step 8. Or we may just be the first ones to the party, so to speak, waiting for other civilizations to catch up. (Jasty, 2014)
All six of these solutions presuppose that Fermi’s Paradox is a paradox. But from the standpoint of weak transcendental idealism, one of the premises of Fermi’s Paradox is false: it’s a mistake to think that we possess no evidence of the existence of other intelligent beings in the natural universe. On the contrary, the very fact that we can have salient empirical and a priori knowledge about the cosmos, entails that we already have encountered all the evidence about intelligent life in the manifestly real natural universe that there is to be had, right here on Earth. If the cosmos is preformatted for creatures like us from the Big Bang forward, then rational human intelligence is all the intelligence there is or ever will be. Simply put, if weak transcendental idealism is true, then everybody is already here, and here is where all the intelligent action is or ever will be.
Upon hearing Fermi formulate his paradox, the physicist Leo Szilard instantly replied: “they are among us and they call themselves Hungarians” (as reported in Jasty, 2014). This was of course intended as a joke, but in fact it’s right on target.
Our existential predicament isn’t that all the alien intelligences out there are hiding themselves from us, but instead that we are the manifestly real natural universe becoming self-consciously aware of itself. Anthropocentrism isn’t a fallacy. Instead it’s an essential fact about the cosmos: its natural laws are all preformatted in such a way as to make rational animals like us us really possible. We didn’t have to exist, but given that we do, and given also that we self-consciously know that, then the cosmos must have inherently incorporated our real possibility from the get-go. The task demanded by our existential predicament therefore isn’t to search for intelligent life elsewhere, but instead to accept with creative piety (see, e.g., Hanna and Paans, 2022) that we are all the intelligence there is or ever will be, right here on this planet or on any other planet we colonize, and then to think, care, and act in such a way as to use our innate capacities properly.[i]
NOTE
[i] This essay is a slightly expanded version of an appendix to (Smith and Stocks, 2025). I’m grateful to Joseph Wayne Smith for inspiring me to re-think my views on the Fermi Paradox.
REFERENCES
(Ball, 1973). Ball, J A. “The Zoo Hypothesis.” Icarus 19, 3: 347–349.
(Bostrom, 2008). Bostrom, N. “Where Are They? Why I Hope the Search for Extraterrestrial Life Finds Nothing.” MIT Technology Review. May/June. Pp. 72-77.
(Britannica, 2025). Lohnes, K. “The Fermi Paradox: Where are All the Aliens?” Britannica. Available online at URL = <https://www.britannica.com/story/the-fermi-paradox-where-are-all-the-aliens>.
(Hanna, 2015). Hanna, R. Cognition, Content, and the A Priori: A Study in the Philosophy of Mind and Knowledge . THE RATIONAL HUMAN CONDITION, Vol. 5. Oxford: Oxford Univ. Press. Available online in preview HERE.
(Hanna and Paans, 2022). Hanna, R. and Paans, O. “Creative Piety and Neo-Utopianism: Cultivating Our Global Garden.” Cosmos and History 18, 1: 1-82. Available online at URL = <https://cosmosandhistory.org/index.php/journal/article/view/1017>.
(Hanson, 1998). Hanson, R. “The Great Filter—Are We Almost Past It?” Unpublished MS. Available online at URL = <http://hanson.gmu.edu/greatfilter.html>.
(Jasty, 2014). Jasty, K. “6 Mind-Bending Solutions to the Fermi Paradox.” Medium. 30 July. Available online at URL = <https://medium.com/o-s/6-mind-bending-solutions-to-the-fermi-paradox-c0f32e47a0f7>.
(Kant, 1781/1787/1997). Kant, I. Critique of Pure Reason. Trans. P. Guyer and A. Wood. Cambridge: Cambridge Univ. Press. (1781 or A edition: Ak 4: 1-251; 1787 or B edition: Ak 3)
(Kurzweil, 2005). Kurzweil, R. The Singularity Is Near: When Humans Transcend Biology. New York: Viking.
(Loeb, 2021). Loeb, A. Extraterrestrial: The First Sign of Intelligent Life Beyond Earth. Boston MA: Houghton Mifflin Harcourt.
(Sandberg et al., 2018). Sandberg, A., Bostrom, N., and Ćirković, M.M. “That is Not Dead Which Can Eternal Lie: The Aestivation Hypothesis for Resolving Fermi’s Paradox.” Journal of the British Interplanetary Society 69, 2: 1–16.
(SETI Institute, 2025). SETI Institute. “The Fermi Paradox.” Available online at URL = <https://www.seti.org/fermi-paradox-0>.
(Smith and Stocks, 2025). Smith, J.W. and Stocks, N. “The Fermi Delusion: Why Aliens Haven’t Called and Probably Never Will.” Against Professional Philosophy. 29 June. Available online at URL = <https://againstprofphil.org/2025/06/29/the-fermi-delusion-why-aliens-havent-called-and-probably-never-will/>.
(Ward and Brownlee, 2000). Ward, P.D. and Brownlee, D. Rare Earth: Why Complex Life is Uncommon in the Universe. New York: Copernicus Books.
(Webb, 2002). Webb, S. If the Universe is Teeming With Aliens … Where Is Everybody? Fifty Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life. New York: Copernicus Books.
(Worden et al., 2017). Worden, S.P. et al., “Breakthrough Listen: A New Search for Life in the Universe.” Acta Astronautica 141: 128–133.
Against Professional Philosophy is a sub-project of the online mega-project Philosophy Without Borders, which is home-based on Patreon here.
Please consider becoming a patron!
