Saying "saucers" don't exist because it is impossible to think they can fail , whatever the reason of the failure , dos not impress me as a rational argument.
Nor me, but I haven't seen that argument from anyone here. Saying that it's likely that one would travel here, only to be brought down by phenomenon that is common to all parts of the universe is much less likely. Every celestrial body has gravity, and some form of atmosphere. In order for an ET vehicle to leave their planet, they would have to understand this concept. Radio waves, magnetic fields, radiation, etc. are not unique to the earth or our galaxy. They would have to understand these principles to acheive interstellar travel aswell. Millitary missles/ballistics? Possibly could bring a UFO down, but compaired to the bombardment of debris that are likely to occur during your voyage through space, they probably would have an answer for that aswell.

Also, assuming that it's early technology and hasn't been refined (like the collapsed pyramids), then what are the chances that we'd be the first place they would visit in order to refine the craft? How did they just happen to come across us in the galaxy with this new, unreliable technology of theirs? It's just not a very likely scenario.

What's even less likely is that something as extrodinary as life from another planet was indeed discovered, but has remained secret all these years. Something that not only changes everything we know about science, but shakes most of our religious beliefs to their core aswell. The biggest discovery in mankind's history, and no one has come forward and been able to offer any kind of proof of this discovery. I mean, I know our millitary officials are well trained and all, but wow.

Occam's Razor--Which is more probable: 1) A conspiracy that (as mentioned) involves the biggest, most belief-shattering discovery of all time being kept secret for forty years, which would have undoubtely involved hundreds if not thousands of scientists and millitary personel. 2) No conspiracy, which is why no one has ever (with any credibility) come forward?

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I'm like one of those idiot savants...well, except for the savant part.