What is the most effective chain of thoughts that a theist can make, that will make him realise that there is no God? Efficiency could be measured in the number of thought steps. I'm especially interested in references to articles that considers question.
Effectiveness should be measured by results. So you would have to look at deconversion stories.
The problem of evil witnessed on a personal and intense level has done it for some. Historical scholarship on the origins of their religion has done it for others. For others again, materialist science leaving ever-shrinking gaps for God to be in.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.