finding extraterrestrial life out there is not impossible, but the probability is very low. even lower than chances of winning the lotto..
but on another thought, we would need to define what *life* is per se. In my "ever-continuing" research on biology, I've come across this really fascinating book on Astrobiology..
Life Everywhere: The New Science of Astrobiology, it opened new frontiers for discovering life from where my previous perspectives on biology were. David Darling discusses different theories on what kind of life we may find out there contrary to our conventional notions of what life is. It could be that we are missing all these other life forms.
but going back to the low probability approach, an analogy I've come across is similar to that of having a credit card number. the chances of you inputting a random credit card number in the hopes of using another's are close to less than 0.00001%. With our current technology on finding life out there, whether its an extinct civilization or still highly thriving, are very inefficient. we'd need to prep our *space eyes* more to eventually find signs of life out there.. a number of space projects have already been generated just for this purpose. the recently launched kepler telescope sole task is this. (or one of its consequential tasks..

).. conspiracy talks..