Sea Breeze: If atheists assume accidental explosions, unguided chance, and chaotic chemical reactions explain of the origins of logic
I don't assume that any of those things explain the origins of logic. That is the strawman. I am pointing out that humans can reason, and we have learned to add structure to our reasoning ability, and this is what logic is. You are claiming that there is more to it than that, and that the existence of logic is dependent on the existence of god. How? How does god "design" logic? How does a universe without god make logic impossible?
Sea Breeze: But, that doesn't make any sense because we all have different brain chemistry, IQ's, experiences etc.
Again, I will point out that this is incoherent. There are many ways in which our brains work the same, regardless of differences in chemistry or IQ or experiences. Explain how these differences would make it impossible for two people to use logic. Don't just claim it; that doesn't address the issue at all.