I have another hypothosis that is rarely proffered. What if we are the first or the only current advanced civilization? Someone has to be first. The odds are against it but at least it fits the available facts. What if the Universe is just too dangerous a place for any single civilization to last very long? Note that we always look for alien life via radio but our own age of radio is rapidly waning. Electromagnetic signal propogation may be completely obsolete in only another hundred years time (I like to envision communications based on quantum entanglement but I don't know if entanglement degrades over time and what that time might be, any physicists out there?), which would leave us with only 200 odd years of radio signals spreading out through the galaxy. That doesn't even count as a blink in cosmic time. The odds would seem to be against any other civilization hearing that little blink unless two civilization were at the same or similar stage of development at the exact same time minus/plus the distance/time for the signal to reach from A to B. Pretty bad odds of that happening. I happen to believe that life may be common but that civilization is extremely rare and fragile. Colonies may be established but a true galactic civilization would seem to be out of the realm of possibility.
I believe you are correct.
We are it, there aren't any other advanced life forms. I suspect alien algae is our most highly developed universal neighbor.
I think you may be right, We could be alone. It's 50/50 isn't it? Everything is 50/50 isn't it. Life is binary. Everything is binary.
The mechanics and logistics of space travel are very daunting. It's a VERY long way to the next place and we may not be able to get there from here. There's no Denny's on the way.
My "touchy feely" new age friends do not want to hear this. Many people want to, need to believe in the magic or other powers or something else other than the absolute banality and mundane ness of their lives and life on our pretty little planet. If there is no one else in the universe, it means we have to take total responsibility for our lives and all our decisions and actions on the planet. There's no one else or thing to blame anything on. It's much easier for some when they have an out. Victim hood is easier. Many are afraid that this is it. Short, sweet and a one way trip.
There are a few articles in the Arts & Letters Daily web site that may relate to some of this, they are :http://www.prospect-magazine.co.uk/ArticleView.asp?Accessible=yes&P_Article=7269 and : http://www.nybooks.com/articles/14796