Good question. Easy answer: I can’t. I don’t know if God exists. Here’s another question. “How can you be sure there is a God?” The correct answer is equally easy:
You can’t. You don’t know if God exists. So we’re really in complete agreement. I don’t know and you don’t know. On this, agnostics and the faithful are as one.
Unfortunately, most believers deny the reality of their uncertainty. And they make an additional mistake by equating these decidedly unequal propositions: There is no God. There is a God. The author of the essay correctly observes that affirming something is true is much different from affirming that there is no evidence of something being true.
I’m confident that fairies don’t exist. You may be equally confident that they do. However, the burden of proof is on you, not on me. I don’t have to prove the non-existence of fairies. Rather, you have to offer proof that they do exist.
Often you hear it said (by those who still believe there were weapons of mass destruction in Iraq, for example) that “absence of evidence is not evidence of absence.” But both the scientific method and common sense are founded on positives, not negatives.
I can’t prove that replying to an email message from Nigeria won’t enrich my bank account by ten million dollars, but I delete it unopened anyway. It’s up to spammers to convince me of the veracity of their pitches, just as it is up to a scientist who claims a research breakthrough to produce the results.
Nobel prizes aren’t awarded to those who say, “Prove I didn’t discover the secret of the universe.” So why is it that the religious faithful are so adamant in asking non-believers to produce evidence that God doesn’t exist? As ex-Christian Dave says:
Someone could state that the Earth is being held in space and spun by giant invisible spirits. Now, before anyone would be expected to accept that belief, they would be well within their rights to ask for some evidence that supports the belief.
I agree that the world is hanging on nothing and spinning. I might not know how the Earth could possibly hang in space and spin, but I don’t believe invisible ghosts on steroids are pushing it in a steady rotation. I might not even have a better explanation than a “ghost theory,” but I still deny that such a thing is true.
It falls to the person who claims to have the explanation to provide the supporting evidence. It doesn’t fall to me to provide evidence as to why I don’t believe in the ghostly world turners. All I need do is state that the evidence presented by the "spirit theorists" is unconvincing.
I need not provide evidence as to why I deny the explanation; I simply deny that the evidence presented is sufficient for me to accept and believe.
So stand tall, fellow agnostics, doubters, heretics, and unbelievers. For testimony to the correctness of our stance is heard everywhere, though it is spoken mutely. When the faithful are asked to provide demonstrable evidence to support a belief in God, their silence says it all.