Einstein's theory of relativity would have to go out the window if there were any differences in the local laws of physics for someone traveling at a large fraction of light speed relative to the Earth...and relativity has had quite a lot of experimental testing. And as long as you can travel at a non-negligible…

Hence 'in a way special pleading', no offense.

Maybe not so interesting, but it isn't "special pleading" since there isn't any well-established general rule that anyone is trying to suggest Earth would be the exception to. We have no idea how probable it is to get from a lifeless planet with conditions suitable for life to a technical civilization, and no real…

That's true—if it turned out to be common for alien civilizations to remain at a Roman (say) level of technology for millions of years, then that would make it much more likely we'd come across a civilization at that level if we could take a peek at our nearest intelligent neighbors. It seems a little hard to believe…

On a related subject, there's a good paper here, discussed in this blog entry from science fiction writer Karl Schroeder, which makes the case that the Fermi paradox is a lot stronger than traditionally believed, and that most of the arguments about how there could be a large number of alien civilizations in our…

I think you misunderstand the filter a little, it needn't eradicate any civilizations, it might operate just by making some earlier step in evolution (say, the evolution of multicellular life from single-celled organisms) improbable enough that we could be the only world that made it past the filter in our galaxy.

Yeah, like I said in an earlier comment, George's statement about the Rare Earth Hypothesis seems pretty ignorant of what the hypothesis actually says.

I don't know if we've really been so lucky, we might have evolved a lot quicker if not for that whole interlude with the dinosaurs, or if it hadn't taken so long for sexual reproduction to arise in single-celled organisms (the first evidence of cells goes back to at least 3.5 billion years ago, but the first evidence…

How could slower-than-light interstellar travel be impossible? Impractical maybe, although something like a von Neumann probe traveling at a very small fraction of light speed could still result in probes having visited every system in the galaxy (and done visible mining/construction projects in each one) in maybe a…

That guy is not only claiming that pulsars are engineered, but that they have been arranged to send messages to (and about) Earth in particular, see this piece by Laviolette:

What are the chances that the evolution of an intelligent alien species would be so precisely synched up with ours that their current level of technology would be just a few thousand years of years behind ours? Given that there have been billions of years for evolution to intelligence to occur, I think the…

Indeed, the idea that the Milky Way is teeming with rocky, habitable planets blows the Rare Earth Hypothesis right out of the water.

Actually the look of the faces in those Renaissance sculptures was intended to imitate classical Greek sculptures, especially the weird nose bridge that almost forms a straight line with the forehead. So maybe the idea is that the Engineers were still visiting Earth in ancient Greek times, and the look of the…

Fair enough, but in that case the stuff about objecting because it sounds like a high school girl, or because it isn't how they would talk in real life, shouldn't really have anything to do with it (and I also don't see why rudeness is any more forgivably "cute" coming from an adult woman than an adult man). Your…

Well, does that mean you only object to the cultural connotations of using "um", not to the slightly rude "you just said something stupid and I am expressing mock-disbelief" meaning behind it? (as it's usually used in typed comments on the internet, anyway) If a British person prefaces a similar statement with "Er",…

Yeah, I thought of the "crossing the galactic energy barrier" scene from Where No Man Has Gone Before too...I guess that makes us the uber-nerds!

Yes, and also to acknowledge that a person is using a bit of humorous exaggeration to convey the mood ("so are you, like, totally done with dating now?") I like "like", in moderation anyway.

It's just a way of condescendingly expressing incredulity at something someone has just said, mildly rude but no worse that posting a picture of Picard doing a facepalm or something—it's the internet, people like to be snarky. And why do you only criticize grown up "men"? You don't hold adult women to the same…

I didn't think he was arguing fencing itself was "doing it wrong", just that the use of fencing techniques in movies set in older times is inaccurate (and would be less effective, perhaps, so from that point of view it might be "unrealistic" in a fantasy setting where swords were used for real fighting rather than…

Thanks for the info! I looked up "From These Ashes" on amazon, and noticed their was also a collection of all his SF novels titled "Martians and Madness".