I think we are still being incredibly self-centered in our thinking. All of our definitions of what life is, what is possible, what is intelligence, etc are based around our collective selfish notion of what we know. But there could be some crazy forms that live, think and communicate but do it in a way that is completely unrelated and unfathomable to how we define "live", "think", and "communicate". They could do so in environments or with chemical/biological compositions unknown to us. They could be more massive or itty bitty - so much so that can't fathom it and we don't have words for it. They could live complete lives or millions of lives in time spans as short as a nanosecond or as long as a bazillion years. Everything is relative to us. Again, self-centered. The closest way I've been able to think about it without completely boggling my mind and resorting to reality TV is through 1 and 2