Half (and that is a conservative number) of all the stars in the universe are binary or multiple star systems. Sirius is the brightest star(system) in the sky. Consider odds.
Now consider the odds that an alien species would be of similar size as us. Live in the same time as us (this brief last 10,000 years or so is but a very, very brief moment on the scale of the universe). That they shredded the laws of physics and created much, much faster than light travel - the sort of thing which would require the energy of a black hole. Not a piece of it, but all of it.
If you make the leap that they discovered a way around time/light/space and got here, if you make the leap that they happened to be roughly the same size as us, and were carbon based "amphibians", there is still the bit about why they would choose to vanish. So you have to tack on a) some sort of holocaust/disease, b) ran out of black hole fuel, c) someone broke their prime directive, and now they went back to observing it, or some other sort of equally....well...sort of reaching scenario.
I'm no numbers man, but stack the odds of what I'm getting at in my first sentence to the odds I'm getting at in the rest.
Really, I'm not trying to be disrespectful - but Occam's razor
Personally speaking, I think that for better or worse, we are alone. I also believe that there is, has been, or will most certainly will be life on other planets. But time on a universal scale is far, far different than the brief history of man, or even of mankind in general. And faster than light travel is mostly the stuff of space opera that truly, is likely to not be possible by any means. I say that sadly, and after having taken a bit of physics and coming to realize that fact.
We're on this rock. Others are on their rocks. The fraction of living creatures that make it to our level of intelligence, and then civilization, are separated by size, distance, vastly different atmospheres and millions and millions of years. That probably sounds awfully defeatist, but its not like in 1200 when we had oceans to conquer by the winds. The distances are simply too vast. We conquered the oceans and populated the world and now we yearn for the stars and companion species - and so our natures yearn for confirmation that we are not alone in the universe. The knowing it isn't enough, and we probably won't ever give up hoping and wishing. It is like a splinter in our minds, for we are an expansionist, exploration, frontier loving species.
Oh hell, I went to rambling.
Short version - its interesting stuff, but I doubt they were visited by aliens :001_cool: