Well, I am unsure where to place probabilities on ET's - I know We have the tech to create "flying saucers" (electrogravitics), and I know We have the tech to create holograms. I do not know whether past civilizations had such tech - could be - and I do not know whether "ET's" carved on things are as old as claimed, are not some representation of electrical displays in the sky, or actual ET's.

The only thing I feel confident in giving high probability (approaching 100%) is that We are on a sphere-ish ball about the size They say. Being able to model things in My head, able to see them from all perspectives, and having modeled the pancake planet, donut planet, a planet We are on the inside of, and others, there is only one - the globe - that explains all of what I see, and does so simply, elegantly, completely.

All the rest require either ignoring observable facts, or convoluting things to the extreme (and which still fall short).

If there are ET's, and if They care about Humanity, I hope They choose to help Us against the psychopaths in control.