That atheism is not rationally justified

[Chas]

I'll defend the position, just for the heck of it. It's not entirely drivel: if some of the quark masses were a bit higher, no stable atoms would form and everything would be a kind of uniform radiation bath with hydrogen or neutrons in it, and nothing beyond that. It would not be a universe with enough structure for a mind to emerge, or Darwinian evolution to take place.

I'm not sure how you make some of the of the quarks masses higher without affecting other parts. If i remember correctly, the quark masses come from the higg's field. Changing the coupling to the higg's field or the vacuum energy of the higgs has other ramifications.

This is not my field of expertise. However, the fine tuning argument only arises if you can change some parameters without affecting others.

The 'fine-tuning argument' is just the Sharpshooter Fallacy writ large.