A sentence that can't have both.

You can't have it both ways.

"You can't have your cake and eat it" comes from Mencius' Fish I Want: "Fish, I want it, and bear's paw also wants it; You can't have it both ways, and you can't have it both ways. "

The original intention is not to say that you can't have both, but to emphasize how to choose when you can't have both, so as to remind people how to choose when faced with choices.

Fish, I want, bear's paw is what I want; You can't have your cake and eat it. You can't have your cake and eat it. Life is what I want, and righteousness is what I want; You can't have both, and you have to sacrifice your life for righteousness.

Life is what I want. I want it more than the living, so I don't want it. If there is nothing more in disgust than death, what can be done to avoid evil that can be used to escape evil? If people only want life, why not use those who can have life? If people are more terrible than the dead, why not treat the sick? If you are right, you are born unnecessary. If you are right, you can make trouble without doing anything. A bowl of rice, a bowl of soup, you can live if you get it, but you will starve if you don't get it. But with disdain to drink and eat, hungry pedestrians are unwilling to accept it; Kick others' food with their feet, and beggars will not accept it.