I am new to natural deduction and upon reading about various methods online, I came across the rule of bottom-elimination in the following example.
I do not understand the step in line 10.
Upon inspection, my initial thought would be that the assumption of ¬p and p both being true is absurd, hence anything can be inferred ( in this case 'p'). However, if this were the case where would you stop (this seems to be an overly powerful tool)? So I assume that this idea is wrong.
Could someone help me understand the rule?
NOTE: I came to StackExchange due to the lack of resources and specific information online.