Athiests do not need proof

Thanks to Pro. Pro has helpfully provided two definitions: Atheist: One who denies the existence of a God/Deity. Proof: Evidence sufficient to establish a claim as true. I do not know the argument my opponent intends to advance in favor of his contention but I think the only reasonable way someone could clam that the atheist need not furnish proof in the same sense as the theist is if they argue, or assume, that atheism is the default position in any debate on the existence of God. This is called "the presumption of atheism". [1] The basic idea is that atheism is the presumed position - just like one is presumed innocent in the court of law. Just as it takes sufficiently strong reasons and proof to move from an "innocent" to "guilty" verdict, it should sufficiently strong reasons and proof to move us from "atheist" to "theist". This all seems reasonable enough until one asks oneself why exactly is it the case that atheism should get this presumptive status. There should be some kind of principle we should be able to derive the presumption of atheism from. 1) The default position is whatever common ground both parties can assent to. (I'm going to introduce imaginary parties just for the heck of it.). So presumably Adina the Atheist and Theo the Theist agree that there is a universe composed of the sort of things found in the theories of physics. Adina says that since they both agree to that common ground and Theo goes beyond it to posit a divine reality therefore Adina's position is the default. But Theo can reply that Adina also goes beyond common ground by saying there is nothing more or nothing over and above the universe. So that can't be a good way to justify the presumption of atheism. 2) Adina unperturbed tries another principle: the default position is the negative one. So whomever is affirming some positive proposition they are put upon to furnish proof their assertion. Theo believes God exists and that is an affirmative, positive proposition; Adina believes God doesn't exist which is the negative position. The problem is this leading to a wide-ranging skepticism if we had to assume for everything that the default position is the negative one and that it requires sufficient reasons and proof to move us from negative to positive. For instance, take a look at the following positions - these are actual philosophical positions, mind you -: The external, mind-independent world doesn't exist, [2] beliefs don't exist, [3] composite objects don't exist (i.e. rocks, stars, your body). [4] No one actually believes these are the default, common-sense positions that require strong evidence to overturn, but yet they are the negative position. And some of these positions (especially the first one) are notoriously hard to refute and many agree while there aren't really any successful arguments against it, it is still reasonable to believe that the external, mind-independent world does exist. So this principle can't be used to establish the presumption of atheism either. 3) Adina has one more principle to try: the default position should be any position that is more probable or likely. Adina would say that theism is more improbable than atheism so therefore atheism should be the default position. Theo would likely be unimpressed by this assertion because it is not at all obvious to him that atheism is is more probable. And this comes to the crux of the problem when assigning prior probabilities to metaphysical positions - it's hard to tell what the correct estimate of probability or likelihood would even be. And that is largely because the process of assigning prior probabilities to some propositions is a subjective matter [5] - it all depends on Adina and Theo's background beliefs. Adina may think the prior probability of God existing is, roughly, 10% or lower, while Theo may think the prior probability of God existing is 90% or higher. Or perhaps Adina and Theo would agree it's hard to even assign a sensible prior probability degree to God's existence. It's hard to establish a default position based on a principle that allows for such a wide variety of subjective prior probabilities. Surely a principle would have a more, well, principled way of ferreting out a default position. This is not all that can be said for the presumption of atheist but, I think, absent that, it is clear that the atheist must provide proof just as the theist does for their respective claims. --------------------------------------------------------------------------------------------------------------------- [1] http://www.philosophyofreligion.info... [2] http://en.wikipedia.org... [3] http://plato.stanford.edu... [4] http://plato.stanford.edu... [5] http://en.wikipedia.org...