# SETI logically proves advanced intersteller civilizations **URL:** \ **Category:** In My Humble Opinion\ **Created:** [March 10, 2014, 6:10pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369 "2014-03-10T18:10:41Z")\ **Posts on this page:** 5\ **Page:** 4
**Author:** ![levdrakon](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@levdrakon](https://boards.straightdope.com/u/levdrakon)\ **Post date:** [March 12, 2014, 9:03pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/61 "2014-03-12T21:03:10Z")
> [@Trinopus](#): > > Oops! Sorry, I thought I was rebutting you. (Embarrassed.) > > David Brin has an amusing argument for The Great Silence: people from advanced civilizations don’t contact us, because they’re all plugged in to their internet equivalent. They aren’t talking to us, because they’re all much too busy sharing pictures of kittens on pianos. I’ve read we’re already moving into that phase. We used to broadcast radio & TV waves all over, but nowadays we confine a lot of that to wires, cables and tight-beam communication to and from satellites. We’re already growing dark, while more active than ever. ---
**Author:** ![Melchior](https://avatars.discourse-cdn.com/v4/letter/m/e5b9ba/32.png) [@Melchior](https://boards.straightdope.com/u/Melchior)\ **Post date:** [March 12, 2014, 9:07pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/62 "2014-03-12T21:07:31Z")
> [@kanicbird](#): > > And they did this by not not getting anything except a on off WOW signal that may be a anomaly. > > This is the argument I have heard and trying to boil it down: > > 1 - SETI has not found intersteller communications looking at the EM spectrum. > > 2- The earth/solar system/sun is not unique, but common and made of common material. Since life happened here, we have to take that life happened elsewhere as well. > > 2a - If we invoke God in this, there is no reason for a god to create life on one planet as god is usually taken as a being of life, so then the universe is already life abundant and it would be not logical for god not to create life everywhere, but back to the basics. > > 3 - Evolution will eventually tend towards intelligent beings due to the advantage of using resources as tools. > > 4 - Using 2+3 we get that there are many intelligent extraterrestrial beings. > > 5 Our Solar System is a newcomer to the galactic party, so plenty of time for more advanced civilizations to have evolved. > > 6 4+5 is there are many advanced beings in all states of their ‘technological evolution’ > > 7 Electromagnetic communications is sufficient for planetary communications but not practical for interstellar communications. > > 8 Since we established that advanced extraterrestrial beings exist and are prevalent in the galaxy we must assume they are not using EM methods of communication, and have found something better, but the only reason for doing so is the need (technological evolutionary pressure) for interstellar communications, therefor interstellar civilizations are a reality and common. > > Yes I skipped a few steps, particularly between 7-8, but that’s the basic gist of it. There is for all \*practical \*purposes \*no \*chance that intelligent life exists elsewhere in the universe. ---
**Author:** ![Frazzled](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/frazzled/32/3368_2.png) [@Frazzled](https://boards.straightdope.com/u/Frazzled)\ **Post date:** [March 12, 2014, 9:42pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/63 "2014-03-12T21:42:57Z")
> [@Melchior](#): > > There is for all \*practical \*purposes \*no \*chance that intelligent life exists elsewhere in the universe. I’ve noticed in other threads that you have very strong opinions based on nothing but your very strong opinions. As mentioned repeatedly in this thread, we have no idea yet how common life is, how long planets can sustain life, and how often intelligent life can develop. The OP was wrong by jumping to the conclusion that intelligent life is abundant but you’re equally wrong to jump to the conclusion that intelligent life is absent. We have no data to support either conclusion. ---
**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\ **Post date:** [March 12, 2014, 9:51pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/64 "2014-03-12T21:51:34Z")
> [@Melchior](#): > > There is for all \*practical \*purposes \*no \*chance that intelligent life exists elsewhere in the universe. How do you know? For all we know there’s an intelligent species on Alpha Centauri. And while they generate plenty of radio noise, the inverse square law means that by the time it gets to Earth it is indistinguishable from noise. But if we knew about them, we could potentially communicate with them using special-purpose lasers somewhere on the EM spectrum. Sure, we’d have to wait 9 years for a reply to our transmission, but so what? Of course, I don’t actually expect there to be human-equivalent intelligent aliens on a planet around Alpha Centauri, or even multicellular life forms, or even any kind of life. All we know is that the probability is somewhere between zero and one. Yes, an intelligent species in the Lesser Magellanic Cloud might as well not exist, since we couldn’t detect it even if it did. But there are lots of stars that are only a few light years away from us. I would say that there is absolutely no possibility of interstellar travel in the next 100 or 200 years, we’re not going to be visiting these guys and sitting down at a quaint multispecies tavern in a seedy spaceport bar. But the bare fact of the detection of the existence of life on other planets–any sort of life, not just intelligent life–would be enormously important. And we may have such information within decades. Or we might not. ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [March 12, 2014, 10:59pm UTC](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369/65 "2014-03-12T22:59:33Z")
> [@levdrakon](#): > > We used to broadcast radio & TV waves all over, but nowadays we confine a lot of that to wires, cables and tight-beam communication to and from satellites. We’re already growing dark, while more active than ever. Realistically, we were never anything but dark. Because, if you take the most coherent laser aimed at space, by the time it reaches the edge of the Oort cloud, about a light-year away (arguably the boundary of our solar system), that pinprick of light will be a disc more than a quarter of a billion miles across, with the concomitant reduction in signal strength. Add to this the interstellar medium (dust and stuff) and solar interference (no signal from Earth will be out-shining the sun, and at a distance, the Earth cannot be distinguished from the sun in line of sight) and multiply that by the much greater beam spread of all our normal transmissions. In EM, we are “dark”, we always have been “dark”, and we always will be “dark”. [Previous page](https://boards.straightdope.com/t/seti-logically-proves-advanced-intersteller-civilizations/683369.md?page=3)