This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Confucius taught that a ruler governs well by moral example: cultivate ren, benevolence, and li, ritual propriety, in yourself, and the people beneath you will be drawn to order the way iron filings are drawn to a magnet, without needing to be forced. Legalist philosophers thought this was, at best, a program for a handful of exceptionally virtuous rulers and, at worst, a fantasy that left every ordinary, flawed ruler with no real tool for governing at all. Han Fei's version of the argument is blunt: a state cannot be run on the hope that its ruler, and everyone beneath the ruler, will happen to be good. It has to be run on rules that work whether they are good or not.
The alternative Legalism proposed was fa, law: a single, publicly known, uniformly applied code of reward and punishment, written down so that no official's private judgment about a particular case could substitute for it, and applied without exception, including, in the most famous demonstration of the principle, against Shang Yang's own patron's family when the crown prince's tutors were punished for a crime the crown prince himself, being immune, could not be punished for directly. Where Confucian government asked people to internalize virtue, Legalist government simply arranged incentives so that the profitable, safe choice and the lawful choice were the same choice, and left virtue as a private matter with no bearing on how the state was actually run.
This was not merely an abstract disagreement between schools. It was a debate about what a ruler is actually able to rely on, and Legalism answered it by asking for less faith in individual character and more faith in mechanism, a wager that a mediocre ruler bound by good law will outperform an unreliable ruler waiting to become virtuous. Qin took that wager for real, applied it at state scale under Shang Yang and later Han Fei's intellectual heirs in the Qin court, and rode it to the military and administrative dominance that ended the Warring States period. Whether the wager was worth what it cost is a separate question the school's own rapid fall from favor after Qin's collapse forced later dynasties to answer for themselves, generally by keeping Legalism's methods while disowning its name.