The Earth as seen from Voyager 1, at a distance of over 4 billion miles.
Surfing through the Atheist Blogroll, I see that Louie at the straightforwardly-titled blog Everything is Pointless has a lovely post quoting one of my childhood heroes, Carl Sagan, on the insignificance of the Earth in the vast universe:
Our posturings, our imagined self- importance, the delusion that we have some privileged position in the universe are challenged by this point of pale light. Our planet is a lonely speck in a great enveloping cosmic dark. In our obscurity, in all this vastness their is no hint that help will come from elsewhere to save us from ourselves, it is up to us. It's been said that astronomy is a humbling and even character building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. For me it underscores our responsibility, our profound responsibility to deal more kindly with one another and to preserve and cherish that pale blue dot the only home we have ever known.Lovely though Sagan's writing may be, and glad as I am to be directed to it, I thoroughly disagree with Louie's conclusion--which might be expected--that this sort of perspective on the Earth shows us that Everything is Pointless.
I don't think Sagan meant this line of reasoning to support this sort of nihilism at all. As I see it, he's making a different point: a subtle jab at religion ("no hint that help will come from elsewhere") and a call for humbleness and human solidarity in light of our basic aloneness in a vast universe--which solidarity would itself surely be pointless if everything is such. But of course this doesn't prove Louie wrong, it just shows that he's making a separate point from Sagan's.
Louie's point seems to be the following, which is a surprisingly common argument for nihilism: our tinyness relative to the rest of the universe proves our total insignificance and the meaninglessness of the things we find important--which are, after all, such tiny things in the grand scheme.
I find this argument interesting because it somehow seems very compelling, but it doesn't actually make any sense.
Why should the size of something have anything to do with its claim to importance? To borrow a point from the philosopher Thomas Nagel: are short people less important and meaningful than tall people? Would we have reason to think ourselves twice as important if the universe were half its size? Surely this is absurd, so why does the size of the universe make us feel meaningless?
I would guess that people think this way because they tend to assume that the meaningfulness of our lives depends on our ability to affect the world outside ourselves. In some sense, that's surely true, but the dependency isn't a linear one: to live a meaningful human life, we have to have meaningful relationships with others, etc., but this doesn't mean that we are only important to the degree that we can affect the outside world. In the same way that the meaningfulness of a book or a piece of music doesn't directly depend on how many people it affects (otherwise the latest Danielle Steele would have to count as much more meaningful than, say, Kafka), the meaningfulness of a human life need not depend on the percentage of the square-footage of the universe that it affects.
But there's a deeper problem here. The premise of this form of nihilism depends on our ability to do something that I believe is impossible: to take a perspective entirely outside of all human affairs and forms of valuation, and then, by applying some sort of "outside" standards, to find all those affairs and forms of valuation to be lacking in significance. I don't think this sort of transcendent perspective actually makes any sense. To find something lacking is to apply our already-existing forms of valuation--the same forms that we are supposed to find lacking! I don't think it really makes sense to turn our intellect in on itself in this way.
In any event, I think it's vital to distinguish between atheism and nihilism. It should be obvious that disbelief in the Sky Fairy shouldn't require disbelief in meaningfulness itself, but many people seem to believe it does. The "astronomical perspective" does, I think, give some limited weight to the case for atheism, inasmuch as it overturns old religious ideas of our place in the universe, but it gives none to nihilism.