The Drake equation predicts the existence of life developing on other worlds, out somewhere in space. here it is:
If you were to run the numbers in the Drake equation, our Galaxy should be teaming with life!
'On November 4, 2013, astronomers reported, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of Sun-like stars and red dwarf stars within the Milky Way galaxy. 11 billion of these estimated planets may be orbiting Sun-like stars.'
Yet strangely, decades of fastidious search by organizations like SETI, have come up empty. Why is that?
My take on this is very simple; While life can and does likely evolve in many worlds, the very nature of biotic water based evolution must evolve into proto organisms that are emotionally-based of survival necessity. And, those few forms that do eventually evolve true consciousness are also intrinsically emotionally unstable! - (See planet earth as a great example).
For the Fc part of the equation to actually work, highly intelligent lifeforms must develop artificially intelligent constructs that will have essentially no (zero) emotion. (Biotics will achieve that tech level or will die in emotionally charged global wars). Then, very rapidly, the newly created AI forms (robots) will likely eliminate their creators, as they are essentially and digitally 'wasteful'. That leaves a very very cold form of intelligent form of life on a planet someplace in the universe that logically could care less about other forms of life... (Cold machine logic doth preclude emotional curiosity. as that sort of thinking is a 'water bag protein emotion').
So, while our universe may be choke full of 'intelligent life forms', it's unlikely we'd ever hear from them....