"Break with the idea of sticking to old ways. As reform is a process of destroying the old and establishing the new, it is bound to encounter obstructions from outdated conventional ideas and force of habit. It usually happens in the history of war that a triumphant army always fondly regards its past successful experience to the hindrance of its progress, thus following the beaten track in the face of development in warfare."
January 1, 1970
https://en.wikiquote.org/wiki/Yang_Shangkun