Upvoted. Heat conduction is involved in the true answer. The student has demonstrated that he at least knows where to start thinking about the question. I'd have more respect for someone who said 'heat conduction', or for that matter 'caloric flow',and tried to work out how that might work than someone who said 'fairies'. Given that this is a question from a physics teacher, you're not wrong to try to find physics explanations before you go to 'trickery', which is exactly the sort of 'explain everything' hypothesis that we're nervous of.
a rationalist should acknowledge their irrationality, to do otherwise would be to irrational.
All you did was show that your argumentative skills were better. His intial belief mentioned souls, and i dont think you ever did. I'd like to see some sort of testability for souls :)
As to your reply of possibly proving his religion false, if he was better at arguing, he may have replied that at the least it might prove his understanding of religion false.
And of course its not as if you have created an AI.