We can’t think we are alone in the universe once we start studying how common our ingredient of life are spread across the universe. The atoms of our body, mainly carbon, hydrogen and oxygen are so common and can be found in every corner of all other parts of the universe. Also not only that, life has got started almost as fast as it possibly could have in the earth, just after it cooled down. Imagine the universe that consists trillions of trillion planets. So thinking about us as the only life in the universe is extremely egocentric.