Until someone can provide evidence that proves otherwise, I choose not to believe in the existence of ancient aliens.
I understand the fascination people have with ancient aliens. The pyramids, the stonehenge, the statues at Easter Island, and even mentions of alien-like beings in ancient text give some credibility to the existence of ancient aliens. However, just as we have no definite proof over the existence or non-existence of aliens today, neither can we prove or disprove the existence of aliens during ancient times.
Don't get me wrong. I'm not saying they don't exist. Aliens might have existed in ancient times. I'm just saying that there's no proof they do, so I would rather not believe in them. Instead, I would rather believe in the ingenuity and inventiveness of ancient humans. After all, isn't it arrogant of us to assume that ancient humans are incapable of building the pyramids and other great structures using only ancient methods and human strength, just because we as modern people require all sorts of technologies to do them. To insist that they needed the help and intervention of aliens is just belittling the human race.
To be fair, I find reading books and watching documentaries about ancient aliens fascinating. However, that's all there is for me--a fascinating topic that I like to explore, not because I believe in them, but because they present wonderful theories. They also make intriguing sci-fi and fantasy stories like the Avengers. I mean, we all like reading comic books and watching movies about the Avengers, but no one really believes in them, do they?
So, do ancient aliens exist? Who can tell? But, while I'm not ruling out their existence, I still choose not to believe in them, at least until I see real proof outside the alternative interpretations of history and doubt on the abilities of ancient humans.