>>11556462Fuck this guy.
There's a standard big jump in difficulty for students in transitioning from the pre-rigorous to rigorous stages, when they might first take fully proof-based courses in things such as real analysis, linear/abstract algebra, point-set topology, etc. One has to develop new ways of thinking and arguing that are unfamiliar to most. However, with enough experience, a lot of this material at the rigorous stage becomes somewhat routine, as one becomes practiced at a lot of the formal manipulations and standard arguments used in these sorts of courses.
The next jump from rigorous to post-rigorous math isn't discussed as much (probably because fewer people get there), but there's definitely another jump in difficulty from standard undergrad material to fully graduate and research-level material where you're expected to be able to fill in a lot of details yourself, accept certain things on faith or intuition (being able to fill in details later if you wish), and quickly jump between different levels of abstraction.
