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Intelligent Life and the Great Filter

By Martin LeFevre

Have you heard of something called “The Great Filter Theory?” It’s the idea that when intelligent life (actually potentially intelligent life) on a planet reaches the level of technology and complexity that human civilization has, most or all extinguish themselves.

The Great Filter Theory is the answer many scientists give to physicist’s Enrico Fermi’s famous question: “Where are they?” He was expressing his surprise over the absence of any signs for the existence of other intelligent civilizations in the Milky Way Galaxy.

In a surprisingly eloquent work conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA, scientists take a very long and large view of humankind’s possible place in the universe, and address what has come to be known as Fermi’s Paradox.

“We postulate that an existential disaster may lay in wait as our society advances exponentially towards space exploration, acting as the Great Filter: a phenomenon that wipes out civilizations before they can encounter each other, which may explain the cosmic silence.”

There are philosophical flaws in the work, relating to anthropocentrism, externalizing human alienation, giving primacy of technological advance, and a lack of a consideration of cosmic consciousness. But “Avoiding the ‘Great Filter’: Extraterrestrial Life and
Humanity’s Future in the Universe” is
an excellent read, not at all “crushing” as the Huff Post characterized it.

I didn’t expect a scientific paper to contain sentences like this one, which has an almost biblical tone: “The Great Filter has the potential to eradicate life as we know it, especially as our rate of progress correlates directly to the severity of our fall.”

So what is “The Great Filter,” and is it anything more than a projection of humankind’s present “polycrisis?”

Given that “nearly every great discovery or invention, while pushing back the borders of our technological ignorance, is all too quickly and easily turned to destructive ends,” the idea (or fear) is that technological civilizations destroy themselves before they can make contact with other technological civilizations.

The notion of a Great Filter grew out of the realization that in a galaxy as huge as the Milky Way, which is but one of billions of galaxies in the known universe, the chances that potentially intelligent life like Homo sapiens is a one-off is mathematically inconceivable. Combine the sheer size and numbers of stars and planets in our galaxy alone with the apparent fact that the universe, despite its general inhospitableness, is apparently “fine tuned” for life, and Fermi’s question is indeed a riddle.

The JPL scientists do not take up the idea that the universe may be “fine tuned” for life. In fact, with flash of eloquence and an indication of where they are philosophically coming from, the authors ask:

“Are humans, just one among the millions of species sharing this remarkably hospitable but fragile oasis in the cosmos, a kind of multiply improbable instance of fused ash first assembling to primitive life then, much later, tumbling into self-awareness followed by spacefaring technological

I doubt it, but some basic questions have to be addressed, and to my knowledge aren’t being asked. For example, virtually all scientists agree that the same physics that applies on Earth and our solar system and galaxy, applies everywhere in the universe. Does the same basic chemistry and biology apply everywhere?

It seems nonsensical to my mind to maintain that the same physics applies everywhere in the universe, but that chemistry and biology can have a completely different basis in different places. Given that the same biochemistry applies everywhere, then single-celled life is undoubtedly quite common, complex life uncommon, and potentially intelligent life like humans rare. If so, we may well find single-celled life in Enceladus, but not on Titan.

And as far as strange creatures go, if and when a planet with complex life is found, will it be any stranger than has existed and presently exists on Earth? From the Earth’s deep past the Stegosaurus comes to mind; from the species with which we share the Earth today (most of which man is threatening with extinction), the giraffe comes to mind. Even the adaptations on ‘super Earths’ would not be stranger than found on our planet’s lands and seas, past and present.

The JPL authors veer off into scientific theology when they write, “The idea of being alone in a universe vaster than our creativity can touch is terrifying to fathom: a feeling of cosmic isolation.”

Why should a universe “vaster than our creativity” be terrifying? And why should being alone, which we have been to this point, and are now? A universe vaster than our creativity triggers man’s hubris, when in fact it should inspire our humility.

Emotions surrounding the idea that we may be alone in the universe are an expression of human alienation and loneliness, not a reflection on a possible fact. The self-knowing human being grapples with alienation and loneliness like everyone else, but he or she does not entertain the idea or indulge the angst of being alone in the universe because one knows what it feels like to be at home on the Earth.

And feeling at home on the Earth, one is at home in the universe.



Martin LeFevre is a contemplative, and non-academic religious and political philosopher. He welcomes dialogue.

Published with permission of the author. All copyright remains with the author.

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