Brother Jason (and others!): With what little we currently know about the conditions necessary to create life, it is possible that we are the only planet on which the right conditions occurred in the right order for it to happen. Also, with what we know about fuel consumption, the age of the universe, blah blah blah, it also takes some enormous hubris to say that if there is life on other planets that they have visited us. In fact, the reasonable person, when asked this question must respond, "We simply do not know enough to even really speculate about that."