I'm probably wrong for all the reasons people mentioned above, but my intuition tells me there is no other life anywhere else, intelligent or otherwise.
Perhaps I'm thinking incorrectly, but for me, it's like looking at William Shakespeare's Hamlet and guessing that due to the size of the universe there has to be another copy of it somewhere else on some distant planet, that somehow Hamlet can be indepedently reproduced on the other side of the universe.
For if life was due to some law of nature then I would expect it to be more prevalent or somehow reproducible in a lab. And as far as I know, all materials we have used to "create" life came from something already living such as bacteria, proteins, etc. In other words, unlike Frankenstein's monster we haven't created life from scratch yet.
So if life is not some law that is easily observable everywhere like gravity, then other possibilities I can think of is maybe we're not able to observe all of life properly (perhaps there are multiple dimensions?) Or maybe we don't fully understand what life is, and perhaps what we thought wasn't alive actually is.
Otherwise, if what we know as life is the only kind, and it's the product of a complicated series of variables combined in a specific set of steps, then it's like assuming that the same series of steps can be easily repeated and all we need is space and time. That to me seems highly unlikely. What would be more likely, to use my analogy, would be someone dropped a copy of Hamlet on a distant planet. In other words, it seems more plausible that all of life came from the same source and spread throughout the universe, our planet being either the origin or itself a recipient of life.
So I'll wait and see if my intuition is wrong.
