Recent scientific discoveries have changed our picture of how common life might be in the universe. We’re discovering new planets on a regular basis. We’re discovering new ways life might flourish in different environments. It seems inevitable that we will soon find concrete evidence of alien life somewhere outside our solar system. Will some of that life be intelligent? And, if so, will it think like us?

Some ancient astronaut theorists are convinced that not only is there intelligent life in the universe apart from us, but that we have already been visited by aliens who have interfered in our earthly political affairs. Perhaps they have ruled over us in the form of ancient gods, waged war on our behalf or used human beings to contest their own battles. One reason ancient astronaut theorists are often met with skepticism is because the common assumption has been that, no, aliens will not think like us. Why would aliens have a distinctly human-seeming interest in earthly power, earthly politics or earthly architecture?

But there are sound evolutionary reasons to believe that if alien intelligent life exists, it won’t be much more intelligent than we are.

Alien genetics will likely employ different molecules than human genetics, but the evolutionary process will be roughly the same. That is to say, aliens will have evolved gradually over time. Just like on Earth, the first alien organisms of antiquity were maximally simple, but varied from each other slightly. Over time, some lived and some died. Those that lived went on to have descendants. Features of alien organisms such as limbs and bodily systems developed gradually. In particular, alien intelligence must have developed gradually.

This is the key to understanding why aliens won’t be much smarter than the average human being. At a certain point in development, the point where we are now, the intelligence and technology exists to solve any solvable problem presented to the species. There may be problems we haven’t solved yet, but the reason we haven’t cured cancer or reversed global warming isn’t lack of intelligence. In addition to intelligence and technology, it takes time and effort to solve problems. Eventually, we will be able to tackle these things.

At this point in the development of a species, there is no need for further development of intelligence. Existing intelligence, in combination with technology, is sufficient. In the absence of any evolutionary pressure towards further development of intelligence, spontaneous variations in intelligence level may arise, but those aliens of greater intelligence will not have an evolutionary advantage over those aliens of lesser intelligence. Maybe aliens will have better technology than we do. Maybe they will have more well-developed memory or skill at judging distances. But their intellect should turn out to be fairly similar to ours.

When we consider ancient astronaut theorists hypotheses regarding how ancient aliens might have interacted with our human cultures, there is a tendency for some of us to assume that aliens must be wiser than we are and so wouldn’t leave evidence behind or wouldn’t make seemingly human mistakes or engage in seemingly human behavior. But if aliens think like us, if they are no wiser than us, just more technologically advanced and well-informed about the universe, anything is possible.