Conservative Christian: If there is no supernatural, how do you define good and evil? If there is nothing beyond this material world of space and time and physics, what are we? Surely the logic which rejects the supernatural reduces us to curious assemblages of complex molecules, ‘living’ on a small rock circling an unremarkable star in the unfashionable western spiral arm of one galaxy in 100,000,000,000 galaxies in the observable universe. You and I, Gary, if you are right, have no value, meaning or significance, for these must come from outside ourselves. Any self-constructed meaning is no better that the ‘superstitous’ beliefs which you condemn.
Gary: You seem to be suggesting that unless I can come up with a better answer for the origin of morality and the purpose of the universe, you win and I lose. But we are not in a contest regarding who can come up with the prettiest, most comforting explanation for all the mysteries of the universe. I for one, search for the truth. And what if the truth is that: The supernatural does not exist; there is no such thing as universal, objective morality; and there is no purpose to the universe. It simply exists.
You might find that ugly and scary but if that is what the truth is, your feelings on the subject are irrelevant. The reason why I don’t believe in the supernatural is not because I don’t like it, it is because there is no good evidence for it.
A recent study found that 40% of Americans under the age of 30 now identify as “non-religious”. Imagine what the numbers are like in Europe! I believe that within not too many generations, belief in gods and devils (at least in the educated West) will be seen as just as silly as belief in witches and goblins.
So how do I define “good”: I should treat others in the manner that I want them to treat me. Sound familiar, Christians? Yes, Jesus said that. He wasn’t the first to formulate that “moral lesson”, but it is a good one. But “do unto others as you would have them do to you ” because it is in your best survival interest (and will make you feel good), not because a god tells you to do it…or else!