Dear rulers ... I maintain that the civil authorities are under obligation to compel the people to send their children to school. ... If the government can compel such citizens as are fit for military service to bear spear and rifle, to mount ramparts, and perform other martial duties in time of war, how much more has it a right to compel the people to send their children to school, because in this case we are warring with the devil, whose object it is secretly to exhaust our cities and principalities of their strong men.