[jacksnipe]

Graduate level logic? That’s so interesting. I only took undergrad, but did an ambitious independent study in logic once; we did not use two-column proofs, which seem mostly useful as a pedagogical tool to make the student see where the logical steps in the proof are, and less as a tool for serious work, since prose is really the best tool for communicating the insights that led to the proof.

Definitely did plenty of “one column” symbolic proofs though. I think part of the lack of need is that seeing two steps right next to each other generally makes it very clear what was done to get from one step to another.

Unless it invokes the axiom of choice, in which case fuck me.