In the master's class I'm currently taking, we've recently set out proving several of the propositions from Book 1 of Euclid's Elements. Here's what gets me:
I don't know what I'm "allowed" to know when doing these proofs. I can't imagine I'm supposed to memorize dozens of propositions, in order, so I know what I am and am not allowed to use on these proofs. I don't even know what straightedge/compass constructions I'm allowed to use, either. I'm dreading the upcoming test, I have no idea what I'm supposed to know and how I'm supposed to get that information.
How the heck?!