Hence the emoluments clause

“Kung-yi Hsiu, Premier of Lu, was fond of fish. Therefore, people in the whole country contentiously bought fish, which they presented to him. However, Kung-yi Tzŭ would not accept the presents. Against such a step his younger brother remonstrated with him and said: ‘You like fish, indeed. Why don’t you accept the present of fish?’ In reply he said: ‘It is solely because I like fish that I would not accept the fish they gave me. Indeed, if I accept the fish, I will be placed under an obligation to them. Once placed under an obligation to them, I will sometime have to bend the law. If I bend the law, I will be dismissed from the premiership. After being dismissed from the premiership, I might not be able to supply myself with fish. On the contrary, if I do not accept the fish from them and am not dismissed the premiership, however fond of fish, I can always supply myself with fish.’ “ – The Complete Works of Han Fei Tzu (trans. and ed. W. K. Liao)