>In our entire human history, we have no proof of aliens, what hasn't happened yesterday, isn't likely to happen tomorrow I think that it makes sense to assume

>In our entire human history, we have no proof of aliens, what hasn't happened yesterday, isn't likely to happen tomorrow I think that it makes sense to assume that aliens, if they ever arrive, will totally reshape pretty much everything on our planet, kind of like invasive species or human colonizers transformed/ravaged where they settle. They won't be interacting very rarely here and there, at the edge of imagination and plausible evidence. You can thereby conclude UFOs aren't aliens if we are able to ignore them. But, conversely, if aliens did ever come to Earth, the logic runs in the opposite direction - they must have reshaped everything and become pervasive in such a way that we don't notice. I think it's a fairly common SF trope that humans turn out to be the aliens, for instance. Or something else familiar is actually of extraterrestrial origin. Assuming that we haven't seen any extraterrestrials so far, I don't see how that gives any security it won't happen. On earth, lots of cultures have suddenly been introduced to others who have more effective technology with devastating results. Keywords/phrases that come to mind are "outside context problem(s)" and "black swans". https://en.wikipedia.org/wiki/Excession#Outside_Context_Problem https://en.wikipedia.org/wiki/Excession#Outside_Context_Prob... https://en.wikipedia.org/wiki/Black_swan_theory https://en.wikipedia.org/wiki/Black_swan_theory I wonder what sort of religious/philosophical response people would have, if it seemed reasonably clear that Earth was unique and the only locus of life in the universe, and also that in the reasonably near future some not particularly exotic object was going to collide with it and destroy all life forever. Does this mean God exists, doesn't exist, broke the promise to Noah, etc? Does anything anyone ever did matter? Is the end of everything human different for an individual than the individual's death? Is it meaningfully different if it happens in 20 years vs 200 years vs 2 billion years? I ask these questions because I can think of a lot of "gut reactions" that are inconsistent with each other.