Just watching a show on cable about astronomy and exploration of space and the possibility scientists say of life out there. (It's so stupid...) So they say they see no signs of life out there, and then wonder if there is life like ours. Imagine that. Life like ours somewhere out there maybe. So it just hasn't "evolved" yet, I suppose. Or maybe these evolved beings look like? a horror being?
The basic issue lies in the area of astrobiology. The question of "IF" there is life in other places in the universe goes back to the question of
"What is life?"
For example, if the idea is that "life" is only what is commonly defined as life on this planet - that is a wide range of possibilities BUT it might not be the reality in other parts of the universe. I.e. there may be something(s) in the universe that doesn't need/require what life on this planet requires to survive.
Further, one could face a sitaution where the only life in the universe, outside of this planet, is only microscopic, liquid based/fish like/octopus like, or plant based. Another possibility is that life in another galaxy may not have human type intelligence. Also, one would have to consider that something that might be "alive" may never be recognized by a human as being as being alive and itself not recognize a human as being alive.
There is also the concept of the Fermi Paradox.
Thus, taking all of the above into account: a) life could be a rare commidity in the universe, b) it could be that one time something that a human could consider to be life once existed in some other part of the solar system, galaxy, or universe BUT it went extinct prior to humans ever finding it, or c) it could be that what is on earth is the first of such a thing.
You also get into the idea that something could use a completely different base of techology that would not be recognized by humans and vice versa. An example that I like is the concept of a Dyson Sphere. There are some who postulate that an advanced society would "probably" build such a device to deal with energy needs. The problem though would be that, for all we know, our sun's outer layer may be a Dyson Sphere from an alien civilization that either a) is extinct or b) we have no way to communicate with and we are beneath its gaze, so to speak, that we would never recognize something that is sitting right in front of us.
Another example, is whether one can consider a planet to be a living creature. If so, currently humans don't have the tools to communicate with something on that level. For example, if the earth were a living being humans may be seen like fleas or germs, etc.
An example here is ants and whales. Ants are very advanced in terms of their societies and abilities, but there are a large number of humans who don't consider ants to be advanced, on a human level, and most humans don't try to establish communication/dialogue with them. Whales have very advanced language and communciations skills among themselves, but there is a human consideration that they are limited by their physical form and their environment.
Until humans are able to set foot in environments outside of the earth, if humans ever are able to or get to that point, much of this is speculation in any direction.