Many recent blog posts continue to try to explain the Fermi Paradox. I'll try to explain why these writers just don't get it. http://enfranchisedmind.com/blog/posts/the-fermi-paradox/
Many people still are confused on several points about the Fermi Paradox. Let's start with the name.
The word paradox is used because everyone "knows" it's a "fact" that there are countless intelligent aliens in our galaxy, despite the fact that none of them have made any obvious contact with humans or visits to Earth. The use of the word "paradox" is sloppy pseudoscience. We don't know, in fact pure empiricism suggests we know the opposite. The complete lack of evidence of aliens in our galaxy is overwhelming evidence that we are alone. The phrase "Fermi Paradox" has become so ingrained that it is almost a single word, and it will be difficult to eliminate it. So I'll keep using it even though I'm convinced there is no paradox.
The reason so many people believe in this "fact" is pure and simple. Darwinism has blinded us to objective science. We all "know" Darwinism is true, and we "know" that it's "easy" for intelligent life to evolve. Therefore we cannot possibly be alone. Let's try to be scientists on this topic. Regardless of your opinion on Darwinism, the obvious evidence is that we are alone.
There is no evidence of intelligent alien life anywhere within or without our galaxy. Look around, and specifically look at other galaxies. We have excellent images of roughly 10,000 galaxies. Not one of them shows an artificial construction. Assuming each galaxy is 10 billion years old, that means that not once in 1e14 galaxy-years has an alien race built a galactic superstructure, visible from our galaxy. Not once. How can any scientist look at this evidence and claim anything other than "humans are alone" ?
And let's be clear, the existence of alien bacteria on a rock orbiting Alpha Centauri has nothing to do with this discussion. I could not care less if every star in this galaxy has primordial life, or even highly evolved tool makers. This is only about intelligent, sentient, technologically advanced space-faring civilizations. Bacteria are irrelevant.
Another point of confusion is the difference between "manned" exploration of the galaxy versus robotic exploration. Frequently bloggers cannot distinguish between these. They say that there are not enough aliens to staff the exploration ships, therefore the exploration of the galaxy will be a lot slower than "commonly" accepted. Again they "know" that aliens would probably not send out self-replicating robots to explore the galaxy.
The fact is that even one self-replicating robotic exploration craft would find every solar system in our galaxy in a matter of 100 million years. That means that for the first few billion years of the existence of the Milky Way no sentient race has built automated exploration craft. Or does it?
A statistical analysis of the evolution of humans from self-replicating RNA demonstrates that evolution is wrong. There are too many permutations available which lead to dead ends. Two billion years on a single planet is not enough time for all the dead ends to be explored. The current theory of Darwinism requires that life "randomly" chose a viable path 99% of the time, instead of a dead end. Most mutations don't work, they result in dead babies, or sterility, or severe biochemical imbalances. Yet evolution on Earth has mysteriously chosen a viable living mutant baby most of the time. What an amazing coincidence !
But what if we combine statistics with the Fermi Paradox? Suppose our galaxy has seen the existence of 1-2 intelligent species that built self-replicating robots. And instead of hardware, the primary substance of those self-replicating robots is biological? Suppose that instead of 2 billion years on one planet, evolution has really had 10 billion years on a million planets. Now the statistics make sense, now we no longer need a miracle of statistics to explain our own biology.
So here's the resolution of the Fermi "Paradox". In the Milky Way (a few million planets over the past few billion years) intelligent life evolved once (or maybe 2-3 times). That species built self-replicating biological explorers which seeded the galaxy. We are the result. Humans are either direct products of alien robotic exploration craft, or we are the first and only intelligent species to evolve in the entire universe.
I prefer the second, I say that the rate of evolution of intelligent life in the Milky Way is about once per 13 billion years. So prove me wrong, with evidence. Real evidence. And don't waste my time talking about what we "know to be true".