Change the terms and see if the logic holds. Say, to evolution.
If in the introductory phase of the idea, someone suggests that evolution should be taught in school, then the onus is on the advocate to prove that evolution exists in order that it may be taught. If, once the idea becomes generally accepted someone suggests that the teaching of evolution should be suppressed, then the onus is on the advocate to prove that evolution does not exist so that it can be removed from the curriculum.
Yup. It would seem that the logic holds.
Look, nobody is ever going to change SD's mind. He is blind to his own bias, and therefore perceives himself as unbiased. Because he believes himself unbiased, there is nothing in this universe that will change is manner of thinking on this.
It is much like the radical liberals living in an echo chamber who feed us the "news" on TV. They are blatantly and radically biased, but they honestly perceive themselves as though they were 'neutral.' SD will remain blind to his own bias no matter what anybody says, and any attempt to demonstrate this for him will only further derail this otherwise extremely outstanding thread.
I have gone rounds with radicals for decades, and I have learned that it becomes important to recognize when you are banging your head on a brick wall. I have come to a point now where I can generally tell by the "character" of obstinacy whether there will be any value in the debate. The only thing that can come out of arguing this with SD is angst for all rational beings.
I have no prejudice against atheists in any shape, way, or form. My closest ally in the RPNC group is an atheist. We get along like gangbusters because I hold no bias or prejudice against her or atheism, and she holds no bias or prejudice against me or my faith.
I recognize that AED does not believe in God, and he probably thinks that I am a bit backwards or maybe even self delusional for believing; but he holds no prejudice or bias against me, and likewise I hold no bias or prejudice against him, and we are fully capable of working together without animosity.
SD creates animosity whenever he encounters Christianity...
specifically Christianity in any shape or form. A rational being will quickly therefore identify SD as the source of the bias/prejudice; but he himself will continue to perceive
himself as unbiased no matter how many mirrors are held up in front of him.
So any attempt at a constructive debate is ultimately futile. Even if he has valid points which can and ought to be discussed, they are veiled behind a cloud of anti-Christian rage, and are therefore inaccessible to Christians. He will simply point to that lack of access as "further proof that Christians are idiots" never seeing that the problem lies in himself.
My advice is to just let him have his last word, recognize that his prejudice is overt and apparent to the vast majority of people reading the thread (even if he, himself can't see it) and put an end to this thread derail by leaving this profitless debate alone.
This is much like the debates to get out of Iraq or Afghanistan. We say that the only honorable thing to do is to bring the troops home now, and they say, "But if we leave NOW then we will be seen as the losers! Cut and run!" Really, the only way to be the loser, is to just stay in those countries and to stay engaged in all this useless violence. We can't win in Iraq and Afghanistan, because our "enemies" (right or wrong is irrelevant here) will continue to fight until the entire middle-east is just a scorched, smoking, radioactive wasteland.
Likewise, right or wrong, SD will continue to fight until the thread/forum is just a scorched, smoking, radioactive wasteland. It has nothing to do with him being an 'atheist' there are also Christians who act exactly like he does. It's just his personality, and there is nothing that any of us can do about it.