I probably don't know about it as much as you do but I think it's true that it implies the egyptians weren't capable of creating pyramids, but I haven't ever considered it being a racist reason, but because they would be technologically inpossible, not saying that it was, just what I thought of when I heard that,
This is the principle of the assertion.
Saying "it must be alien that constructed pyramids" implies that egyptians didn't have the capacities to do them. This implication is the result of the invisibilization of all the technological prowess of non europeean societies. Colonialism is not only a system of domination of a culture over another but it's also the deshumanization of the dominated culture.
Colonialized people were (and still are in one specific country of the world) "barbarized". In such a way that their technologies were appropriated and their cultures erased. The vision of the culture you usually know from the west, let's say from games like Assassin's creed for example, are usually westernized vision of the countries. Visions that are fantazised ones and mainly devoided of agency.
A simple testimony of that can be seen in a video that was shared a few weeks ago:
In this video, you start to understand that "oriental music" has pretty much nothing to do with actual middle eastern music and is really just a fantasized and post colonialistic vision of the art and music that westerner have of those country.
It's the same for technology and scientific advancement, but in those case, our fantasized vision is that non-europeean civilizations were mostly archaic and devoided of relevant technology (relative to our own in the west)... So combined to pseudo scientifism..
People started to believe that Pyramids were created by aliens and that ancient Astronauts visited us in the past.
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I fell in that trap my self when I was young. I was fascinated by the legends of the crystal skulls and the ancient astronauts theory this is what led me to complotism and toward very weird ideas. Once I started to research (for myself) the technological levels that could reach certain ancient civilizations... I started to understand that the west wasn't as technologically advanced as I was educated to believe.
Just an example:
Do you know the
Qhapaq Ñan ? It's a network of paved road created by the Inca on the basis of an already preexisting system before them. It is said to be around 40 000 Km long.
"
The road system allowed for the transfer of information, goods, soldiers and persons, without the use of wheels, within the Tawantinsuyu or Inca Empire throughout a territory covering almost 2,000,000 km2 (770,000 sq mi) and inhabited by about 12 million people" - Wiki.
This might be nothing to us now, but this is huge for precolonial civilizations.
Our world is filled with amazing discoveries all over.. But we need the knowledge we know through a anti-colonialist lenses to understand that the west was actually just amazingly imperialist, not amazingly advanced.