For wizards focused on seeking truth from the outside world, even mind magic is built upon the analysis of rules and orders.
No wizard would suddenly become strong due to a burst of willpower during a battle. This is the fundamental difference from the later debates of idealism and materialism, and has three points of similarity.
This is why spellcasters must find a feasible path and establish a general framework, using the feedback from laws to prove that their direction is correct. Only then can they merge the crystallization of their wisdom and inspiration with the divine, completing the final transformation through sublimation.
One advances on the right path, while the other can skip classes and make them up later. This is the difference between spellcasters and war professionals.
Perhaps in the future, spellcasters will find ways to bypass this condition, but currently, none exist.