From a numbers perspective, it’s highly likely that humans aren’t the only intelligent beings in the universe. In fact, NASA’s chief scientist (Ellen Stofan) recently asserted that while humans are likely to find evidence of intelligent life within the next five years. Whether we’re ready as humanity to accept the implications of the findings is cause for a lengthy discussion.

In the event Stofan’s prediction comes true in the near or long term, the odds that the first evidence of discovered life will be “intelligent” is rather slim. However, that doesn’t mean that intelligent life does not exist.

In fact, given the size of the known universe (93.016 billion light-years in a sphere), it would be close-minded to believe that humans are the only intelligent beings in the universe.

To that end, there are five primary possibilities about humans’ place in the hierarchy of intelligent beings:

1. Humans are the only intelligent beings in the universe.

2. Humans are the only intelligent beings in the universe (though other civilizations came before us and no longer exist).

3. Humans are the least intelligent beings in the universe.

4. Humans are the most intelligent beings in the universe.

5. Humans are among many other intelligent beings in the universe, and humans are neither the most or least advanced.

It is my opinion that the fifth option is most likely. Consequently, if there are more advanced beings somewhere out there beyond the reaches of our galaxy, it is prudent to ask where humans fall on the spectrum of capability.

Fortunately, in 1964, Soviet astronomer Nikolai Kardashev proposed a way to classify civilizations. Now known as the Kardashev Scale, Kardashev proposed that civilizations could be grouped in to three distinct classes of technological advancement by using the amount of energy it is able to harness and use as a proxy.

 The scale has three designated tiers:

• Type one civilization: Can use and store all of the energy available on its planet and harness of its resources.

• Type II civilization: Can use and control energy at the scale of its solar system. At this point, humanity will have long abandoned fossil fuels to rely solely on solar and renewable energy sources and are also capable of inter-planetary travel.

• Type III civilization: Can control energy at the scale of its entire host galaxy and harness the resources of the entire galaxy.

Carl Sagan placed humanity at a 0.73 on the Kardashev scale… so there’s a fair amount of opportunity for humanity to evolve.

On the other hand, in the event a higher-tiered civilization notices humanity’s existence on Earth and is able to traverse the vast distances between galaxies to Earth, let’s hope they’re peaceful. However, that’s a post for another day.

-Adam

Sidebar: Most, if not all, of the elements on Earth are plentiful on other non-inhabited asteroids, comets, and planets. (For example, the interior of the planet 55 Cancri e is believed to have a surface that’s mostly graphite surrounding a thick layer of diamonds.) As a result, it’s likely easier for intelligent beings who seek such resources to harvest materials from locations where intelligent life won’t be disturbed in the process. Something to think about for the game theory lovers out there…