Translating mathematics into code that a proof assistant can understand is a process that involves a fair bit of friction. There’s quite a big difference between what humans are willing to suspend disbelief about, and what a type checker will actually accept without proof. Reducing this friction is the primary task of the authors of a proof assistant — but, of course, it would be infeasible to modify the proof assistant itself to cover a new problem domain every time one comes up. To this...
