My recent post on the proposition that agnostics were about as much use to the world as a bicycle to a fish created the usual dichotomy of response (one responder suggesting it was people like me who gave atheism a bad name). I thought it was worth following up with a somewhat more expansive explanation.
There are many things in life about which we can be absolutely certain - gravity comes to mind, and the evolution of the Galapagos finches, and the circulation of blood, and the importance of gun control. Nobody could fail to believe in these things, and someone who was "agnostic" about them might well find themselves flying from a tall building or being shot in a dark alley.
On the other hand there are many things that no one could believe in - George Bush as a great President, a 6000 year old Earth, the Earth balanced on the back of a tortoise, Fox News as a fair and balanced place for political debate. So, no room for agnosticism about any of those, or you might start thinking there were WMD in Iraq, or find yourself up to your eyebrows in turtle poo.
But there are many things one could be agnostic about. Here is an example. Would Barack Obama be a progressive or a conservative (with a small c) President? There are people who passionately believe that Barack is the re-incarnated JFK and would govern in the same enlightened and liberal way as that great man. There are others who equally passionately believe that Obama differs from Hilary Clinton only in being black and male, and would be just as much a creature of the corporations and the DLC as she would. Both beliefs are passionately held, both can draw on much evidence for both conclusions, both have been vigorously argued by some of my fellow HuffPo bloggers. But neither proposition can be proved, and the third belief one could hold (which I hold), is an agnostic one that we don't have enough evidence either way to be sure, and that we won't really know until he is well into his first term as President.
Another poster gives an example of agnosticism in relation to whether there is life elsewhere in the universe. And this is interesting but as a kind of reverse of the situation with religion. Let us look at it. There is no direct evidence that life exists elsewhere in the universe. You could then simply deny that there is any other life, or you could believe there is and that the evidence will be found sooner or later. Or you could say: We know life arose once on this remarkably unremarkable planet. We now know that other stars do indeed have planets. And we even know that there are stars with planets that are potentially Earth-like in size and position relative to their own star. Since we can observe very few planets, we can deduce that there would be many billions more of such Earth-potential planets. An agnostic might say "well, chances are, that means there is highly likely to be life on other planets". "On the other hand" our astronomical agnostic might say "it could be that the chances of life evolving on Earth were very small, and therefore by chance it may never have arisen elsewhere". So you could certainly be genuinely agnostic about the chances of life elsewhere in the universe (just as, in a closely related topic, you could be agnostic about whether UFOs have visited Earth).
But there is simply no comparable position in relation to a "god". No equally balanced sets of data, no probabilities to be evaluated. There is, simply, no evidence of any kind, for a "god". Indeed the total lack of evidence is seen by religions as a plus, because the less evidence there is, and the sillier the beliefs, the more faith is required. And faith, they think, trumps rational thought. Only in sheep, say I.
That is, to be an agnostic about anything requires evidence both for and against a proposition, with the agnostic balanced equally between the two. This doesn't mean a balance between "there might be, prove there isn't" and "there isn't, you prove there is", those are mutually exclusive ways of looking at the world. This whole debate about agnosticism is interesting not because of agnostics themselves, but because of the insights it can give into how we know about things, why we believe in things.
The scientist starts with the strongest belief of those things for which there is the most data, gained from experiment or observation, and as he or she moves down through subjects with less and less data, so the scientist accepts them less and less. The religious follower on the other hand has the strongest belief for things for which there is no evidence, and as he approaches subjects with strong scientific backing, utterly rejects them. Those who say they are agnostic about religion, need to think about which of those scales they belong on.
So keep your agnosticism for politics, where it is healthy (I don't think a passionate faith in any politician is good for democracy). But in relation to religion? Either come into the church or stay out, but don't stand in the doorway or block up the halls.
Want to graduate from agnosticism to atheism? Try the Watermelon Blog.