Ask your atheist or agnostic friend to consider the following scenario and then consider at what point she would conclude that God had answered the prayer and thus that God exists.
So here’s the scenario. Your friend calls you up to say that she just received an unexpected bill for $4353.43 which must be paid this week or she will be evicted from her home. So you say, “Why don’t we pray about it?” She looks incredulous so you add, “Hey, what do you have to lose?” Begrudgingly, she concedes that it is worth a try and so you pray, “Lord, please provide a means for my friend to pay her bill!”
Later that day, your friend goes home, opens her mailbox, and sees a letter from a lawyer. She opens it up and discovers a check in her name from the estate of an obscure relative that she has never met. The check was mailed one week ago and contains a sum which she can use to pay off her debt (or some portion thereof). Which of the following amounts would be sufficient to persuade your friend that God possibly exists, that God probably exists, or that God definitely exists?
The more one is willing to check “Definitely exists,” the lower their skepticism. The less willing one is willing to check at least “Possibly exists,” the higher their skepticism. Thus, the person willing to say that God definitely exists after receiving a surprise $4000 check has a relatively low threshold of skepticism. Meanwhile, the person who dismissively attributes even a check of $4353.43 to chance, and thus who is unwilling to concede that even this specific amount would provide reason to consider that God possibly exists, has a very high degree of skepticism.
The question is, where on this chart is the rational threshold in which it is proper for one to move from doubt to the possibility, probability, or actuality of God’s existence?