So here is the setup: I know a bunch of people who think it is the dumbest thing ever or absolutely ridiculous to say, "I don't believe aliens exist." What is your stance on that question? Here is what I currently know: +I have seen no evidence for alien existence Therefore, I don't believe in aliens. Now, if there is some evidence, I would change my tune. That is partly why I'm making this thread, to make sure there is no evidence as I have encountered. Here are some common arguments for alien existence: +Drakes equation Giving names to unknown probabilities does not mean we know them. Don't make me laugh. +"Pyramids! Therefore, aliens visited us, and by extension, aliens exist (since non-existent beings cannot visit us). First off, arguments of this flavor basically say, "We have no idea how [...]. Therefore, we do know how [...]." Ridiculous! The conclusion and premise are exact 180s of each other. As a demonstration of the insanity of this argument, consider the possibility of ultra-advanced humans coexisting with "tribal" humans, oh, for example how Americans coexist with small tribes in the middle of the Amazon jungle. +"Space is SOOO huge! Therefore, aliens must exist." This is a funny one. To this, I ask, "What is the probability of life spontaneously generating per unit of space"?" Without that probability, the number of trials for spontaneous generation mean nothing. In other words, (unknown probability of life generation per unit volume)*(known volume) = unknown expected value of instances of generated life. +"Space is INFINITE. Therefore, aliens must exist." This one tickles me more than the prior. It is extra misleading, because it is a valid argument. Given any nonzero probability of spontaneous generation of life and an infinite number of trials, life must have come about elsewhere. However, the premise that the universe is infinite is not known to be true as of now! So the conclusion based on it is dubious. I would go so far as to believe that premise is unprovable since it would take an infinite observation to verify something is infinite. Please help me not be an idiot. I have way too many people telling me I am. Thank you! I have even seen astrophysicists and astronomers on T.V. (albeit possibly sensationalists) say "OF COURSE there are aliens out there." When they say this, it makes me wonder how they know so steadfastly.