Recent Theory, the “Great Filter” Suggests Aliens Keep Destroying Themselves Before They Can Spread — Here’s Why That Could Spell Trouble for Humanity

Have you ever wondered whether aliens are real or not? Well, most scientists think they exist, so the question they focus on is, why have we not met any of them yet? For a universe so big, it also feels so empty. However, the fact that we are here could mean there are also others out there, right?

There are a lot of theories answering all these questions, but the one we’ll discuss in this article is called the “Great Filter”. It states that there are specific reasons, or rather, hardships, as to why we have not met any aliens yet. This is a theory that will make you pause, because it also heavily talks about the future of human civilization.

What Is the “Great Filter”?

The “Great Filter” is an idea or a hypothesis presented by economist Robin Hanson in his work, titled “The Great Filter – Are We Almost Past It?”. Hanson asked the same question we have today, years later: Why have we not seen alien visitors or messages? He theorized that there might be a specific reason stopping them, and that reason could be what he called the Great Filter.

The theory suggests that there are steps that are hard to overcome in the evolution of an intelligent species. Transitioning from simple forms of life into an expanding, space-faring civilization requires an almost impossible breakthrough. He presented several steps that any species must pass to continue surviving; however, one or a few of these steps must be super rare, or else, we’d see more alien civilizations by now.

Read more: Mason

The Nine Steps That Might Block Life

Brian Cox - Alien Life & The Great Filter Hypothesis

Hanson outlined nine key steps that any civilization needs in order to spread into the galaxies or progress as a species. First is the right star system. As we know, without our sun, life would have never existed here on Earth. A habitable planet at just the right distance to its star is also a requirement. It must not be too close or too far away from its sun.

From here on out, Hanson followed how life developed on our planet. So, the 2nd stage was the development of RNA or reproductive, self-replicating molecules. 3rd is the emergence of a simple single-cell lifeform, known as a prokaryote. 4th stage is the advancement from single cells to more complex organisms, called eukaryotes.

The 5th stage is where various forms of life start to develop because of genetic diversity and increased speed of evolution caused by sexual reproduction. The 6th stage is the evolution from single cells to multicelled organisms. The 7th stage is where most species on Earth are still stuck, and that is the development of tool-making capabilities and their utilization.

The 8th stage is where the current modern humans are, and it refers to the rise of a civilization that has the technological ability to dominate their planet and begin space colonization. The 9th and last stage is what’s needed for us to see or meet any alien civilization, if they are out there, which refers to a civilization capable of expanding into space or interstellar colonization.

Why We Haven’t Seen Aliens Yet

Hanson theorized that most species or planets get stuck in one or a few of these steps. It could be the early steps where intelligent life is not yet present, and they are having a hard time evolving from a simple life form. It could also be the one ahead, where they are trying to survive technological failures.

He suggested that if even just one of those steps is missing, or a species could not pass them, then that would explain the silence we are facing. Maybe most of the aliens out there are still just tiny single-celled organisms, or just like us, they do not have the capability yet to travel near the speed of light to visit other planets.

Read more: Research Gate

Self-Destruction: A Filter of Our Own Making

The Great Filter Hypothesis With Neil deGrasse Tyson - The Solution to The Fermi Paradox

A species having to pass all those nine steps in order for us to meet them, or the other way around, is why it is called the great filter. In other words, one of those steps serves as a massive roadblock explaining the absence of any observable alien life forms.

What’s terrifying about this theory is that we are not sure if we have passed those filters yet. If the hardest filter is actually in our past, for example, the transition between single cells to a more complex organism, then we may have a clear path ahead as long as we do not destroy ourselves.

However, if for some reason the hardest filter to break through is the 8th and 9th stage, where we currently are, then our continued survival is still far from certain. It meant that other civilizations may have reached our stage too, but something caused their destruction. Some reasons could be climate collapse, nuclear war, or uncontrollable AI.

The Great Filter is not a scientific fact but rather an educated thought experiment, modelled after our very own evolution and progression as a species. Scientists are still looking for any signs of past life forms on different planets, whether they reached the 3rd stage as a single cell organism, or they were in the 8th stage and became a technological civilization. This will help us figure out what stage or where the hardest part of the great filter is.

Hanson’s Great Filter theory may or may not be true, but it did one thing. It made us realize just how fragile life is and how impossible the steps are. The silence we are facing could very well be because we are one of the few, or worse, that we are alone in this whole wide universe.

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