milky way
Humans have had a great ride. We've overcome vicious predators, drastic shifts in climate, diseases, large-scale warfare and many other things that would have put an end to lesser species. These days, life is so comfortable and sheltered for many of us that we often take the survival of our species for granted. However, as I will discuss in this article, there is a major risk of extinction on the horizon. Will we overcome this hurdle like we have overcome past hurdles, or will our species finally be filtered out?

To understand what I mean by a "Great Filter", let's first go over the Fermi's Paradox. The Fermi's Paradox is the apparent contradiction between the lack of evidence and high probability estimates for the existence of extraterrestrial civilizations. To put it more simply: if there are 70 sextillion stars (more than all grains of sand on earth) in the observable universe, why haven't we discovered signs of intelligent life? The odds of such a discovery should be heavily in our favor.

We have gotten some close calls, like the mysterious SETI signal we got 40 years ago, and the possible alien megastructure (I.e. Dyson Sphere) discovered a few years ago. But these discoveries are far from conclusive signs of another intelligent civilization.

There are many possible explanations for why we can't find intelligent life. Here are a few:
  1. other civilizations might be out there but are too advanced to communicate with (think about a human trying to communicate with an ant),
  2. intelligent lifeforms could have already visited or tried to communicate with Earth, but we were not here yet,
  3. higher civilizations are aware of us but are just observing our species for now,
  4. the concept of physical colonization may be a silly idea to higher-level civilizations (therefore, no need to find life elsewhere).

The possible explanations above could very well be true, but I want to consider the possibility that intelligent civilizations are so rare that we may never find another one; no matter how advanced our search techniques become. If the reason we cannot find intelligent civilizations in the universe is because they are extremely rare, there would have to be daunting hurdles in the way of the evolution of all civilizations. This is the concept of the Great Filter.

The Great Filter
As I said above, humans have already made it through significant filters that other species did not (e.g. Neanderthals). We have adapted well enough to our ever-changing and often violent environment to reach what we consider modernity. We have wireless communication, far better medical care than we've had for most of our existence, immense educational resources and a thorough understanding of the natural world. However, according to the Kardashev Scale, we haven't even become a Type I Civilization yet. This means we can't harness all the energy on our planet. Type II is when a civilization can harness all the energy from their host star. Type III can harness the energy of the entire galaxy. Obviously, humans have a long way to go.

In my view, the Great Filter clearly lies ahead. I believe the Great Filter will be the inevitable clash between human nature and technology. And I'm not necessarily talking about a Terminator scenario, although it is possible.

Think about the human species' unquenchable thirst for war. The Vietnam War, WWII, WWI, the US Civil War, the Taiping Rebellion, the Ottoman Wars, the Napoleonic Wars, the Seven Years' War, the Thirty Years' War, the Spanish Conquests, the Mongol Conquests and the list goes on and on and on. War appears to be an unavoidable part of human nature.

Now, think about the exponential growth in technology, especially weapons technology. From sharpened sticks, to stone weapons, to metal weapons, to projectile weapons, to bombs, to planes, to tanks, to nukes and now to artificial intelligence. Our thirst for war, combined with the exponential growth in technology, has made us too efficient at destroying humans. It has made us so efficient that if the world's superpowers fought with the kind of vigor they had in WWII, they could easily destroy all life on earth.

As a species, we haven't turned off our thirst for war, but with our current technology, our thirst for war will turn off the species. This is the imminent conflict between human nature. If this is not the Great Filter, it surely is a significant filter that will determine whether or not we have reached the end of our evolutionary path. Because our species has not had to comprehend this conflict before, no one knows quite how to handle it. Let's hope we all do the right thing so that our species may move on to bigger triumphs.