Have you ever seen the "existence of God vs. existence of Spider-Man" image floating around on blogs and the internet? Whether Christian or atheist, you can't help but laugh at this. Of course, we laugh for different reasons. But who is thinking about this correctly?
The atheist looks at this and says, "Ha! There is no God, otherwise you Christians must admit Spider-Man exists (which is clearly ludicrous) because of this 'equal and opposite' book that has Spider-Man in it!" But is this really a good argument?
Often a Christian will look at this and laugh for an entirely different reason: this analogy is a poor one.