Can you prove that a god doesn’t exist?

Hellmut’s recent comment on ontology was so good that I think it deserved a new post. We have a distinct lack of evidence that dogs can’t fly. But can we prove it? Hellmut explains:

Actually, you can’t prove that dogs can’t fly. Somewhere in the space-time continuum, there might be a dog that can fly.

The precedence for that insight was Francis Bacon’s famous statement about white swans. Since every swan anyone had ever seen had been white, Bacon concluded that all swans are white.

Then we discovered black swans in Australia.

Logically, we cannot prove universal statements, i.e. claims about anything that is supposed to always be true.

Likewise, we cannot disprove existential statements because somewhere, sometime beyond the current reach of our senses, there might be a purple cat with five eyes and seven legs.

It’s the old adage: You can’t prove a negative. And in fact, I wouldn’t try. I’m an atheist because I find the claims of theism lacking in evidence, not because I’ve proven the non-existence of a god.

But this is only partly true. Some negatives can be proven. I can say for certain that there are no square circles. I can also say that there are no married bachelors. (Not unless we redefine those words beyond conventional recognition.) The existence of these things would entail a contradiction in terms, and that’s not allowed.

What about a god? Well, the concept of god is defined so poorly that I can’t be sure that there isn’t one lurking around in this big universe of ours. But I can be quite sure that the Christian god does not exist. According to the claims of its believers, such a being would entail some logical contradictions:

• He would be all-loving, yet condemn people to suffer eternal punishment.
• He would know the future before we do it, yet allow free will.
• He would be able to do anything, and yet not. (Ever hear the one about god making a stone so big that he can’t lift it? Oh, you have.)
• He’d be all-good, yet allow unspeakable evil to occur.
• Wouldn’t being all-good and all-powerful make him powerless to do evil things?
• I suppose that’s not a problem for the biblical god, who does evil things all the time, but then that raises omnibenevolence issues.
• And he would be perfect, yet somehow need to be worshipped.

There’s nothing new about these contradictions, and people have tried to resolve them with varying degrees of success for a long time. Yet they persist.

It’s all very easy for me as a ‘weak atheist‘ to sit back and demand evidence, especially when believers refuse to provide it. Having done that for a while, I’m now feeling an urge to assail the problem on its own turf and make some claims of my own. Consider this, then, a tentative exploration of the boundary between weak and strong atheism, and a possible avenue for the disproof of a particular deity, even if it’s not a blanket denial of all possible gods in the universe.

Required viewing: