Which is more likely...
That people back then, people that are just as clever as people today, figured out a way, (they had a whole nation of people that could work on the problem!)

-OR-

That an alien race showed up, helped them set up obelisk, maybe did a few other things, then erased all evidence of their passing, but forgot to account for the fact that people thousands of years later might question how these ancient egyptians raised these large obelisk? And only passed on basic knowledge of moving stone around instead of, ya know, advanced space faring technologies? Or even anything in between? Leaving us poor pitiful humans to discover things like penicillin, clean hygiene practices etc?

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Sure you can argue a particular technique thought up today of how people did it, is in error, but it is a more grievous error to immediately assume that it was aliens that did it, instead of possibly some other yet to be discovered technique.

One theory I heard is they made a very large pile of dirt, rolled the obelisk up it, then slowly and carefully removed the hill in a way that left it standing upright. They probably screwed it up a bunch before they perfected it. But, a lot can get done with 10's of thousands of slaves. If they can transport a very large stone for miles, they can also transport such a large stone up a slight hill for a few hundred feet or take advantage of a slight down hill to build up the dirt and not even have to push the obelisk uphill.

With how many planets there are and considering that we managed to evolve and adapt to the changes in our atmosphere, I feel it is highly probable that there is life on another planet, even if that planet might have an atmosphere that is toxic to us or a climate that would not suit us. I read somewhere that one of Saturn's moons might have life underneath it's icecap because of thermal vents which was one of the conditions for life on our planet. Who knows? It would be cool if we could discover extraterrestrial life in our lifetime, though with our current rate space exploration, I don't know if it ever will be. But I feel in years ahead, it will be discovered.

Alien low level life forms exist on Planet Earth. Intelligent Beings exist on Planet Earth. Which are you?

Nyarlathotep is the perfect example of a low level life form existing, interacting and taking up SPACE on Planet Earth.

He is such a low level life form he cannot look up two words in the dictionary(Existence and Being) He is unaware of the environment he lives in, like a person in a comatose state of mind, who lacks objectivity.

Etymology of those two words require Objective Reality to exist in both fact and state for intelligent existence to occur.

You are looking into outer space for intelligent existence, when you should be looking into the mirror at yourself to determine it..

I am a scientist, a physical physicist.

TIME is;
Physical measure of SPACE occupied by
material MATTER existing in TIME, the continuum.
You, are a fixed point in TIME, the continuum.
1 a fact of living
2 a fact of objective reality
3 a state of living
4 a state of objective reality
If you live and observe "Relativity" in Albert Einsteins Relative Reality you are not a intelligent being.
Einsteins Relative Reality precludes intelligence by definition. You can still exist as is, or like a comatose person exists, unaware.
My physical tangible Newton physics formulation will allow someone to prove their existence as an INTELLIGENT BEING EXISTING in the Universe, in TIME, the continuum.

Can you do it?
Stop trying to seek something, that is speculation.
Truth is sought by police investigators, of the facts that are known and facts that are provable.
Intellectual Property of Michael Alan Chapman
Chapman Metaphysics/Material Existentialism California USA