Burden of Proof
Anyone who has taken even an introductory course in philosophy will tell you that the burden of proof always rests with the side making the claim. The theist claims that there is some sort of god; the atheist does not accept this claim. The burden of proof belongs to the theist. If you want us to believe that your god(s) exist, make your case.
Educated believers generally accept this burden but attempt to sidestep it through faith. Since they realize that there is insufficient evidence to support their god claim, they resort to faith. Some even try to turn faith (i.e., the acceptance of a claim without sufficient evidence) into a virtue.
Less educated believers may actually ask atheists to prove that no gods exist. In such cases, it may be necessary to teach them about the burden of proof and use examples with which they can relate. With patience, it is often possible to show them that their request was misplaced.
The Role of Proof in Evaluating Religious Claims
In addition to helping the theist understand their burden of proof, it is often helpful to consider that "proof" might not even be the correct standard here. I would argue that the problem with believing that some god(s) exists is not that the existence of such a being or beings cannot be proven; the problem is that there is insufficient evidence to justify the belief.
Not all atheists will agree with this, so let me be very clear about what I am saying here. I can accept the idea that someone could believe something without having absolute proof in the object of one's belief. As long as the evidence adequately justifies the claim, it need not rise to the level of total proof in all cases. Clearly, this means that the nature of the evidence needed will vary with the type of claim being made.
If I claim that I regularly walk to my mailbox to get the mail without wearing shoes, you may just take my word for it and require minimal evidence. On the other hand, you are right to ask for considerable evidence to support my claim that a supernatural being punishes sinners with hurricanes while rewarding homophobia with Republican votes.
The bottom line is that atheists need not entertain requests for proof of atheism from believers. It is they who have the burden of proof, and if not proof, then sufficient evidence to justify their claims. That they they have been unable to come close to meeting such a burden is all the "proof" atheism needs.
Subscribe to Atheist Revolution