A law-book never recites the utility, the grounds, the casuistical antecedents of a law: for if it did so it would lose the imperative tone, the " thou shall, " on which obedience is based.

法律书从不背诵法律的效用、理由和因果关系：因为如果这样做，它就会失去命令语气，即服从所基于的“你应”。