1. Listening is bright and listening is dark. 2. "Listening is clear, but the letter is dark" is Wei Zhi's advice to Emperor Taizong. In the Tang Dynasty, Emperor Taizong asked Prime Minister Wei Zhi: "As the king of a country, how can I distinguish right from wrong and not be deceived?" Wei Zhi replied: "As a monarch, only listening to one side of the story will confuse him and often make wrong judgments. Only by extensively listening to opinions and adopting correct opinions will we not be deceived and will we clearly know the following situation. " 3. It means that in order to understand things correctly, we should listen to opinions from all sides at the same time; If you only believe one-sided words, you will inevitably make one-sided mistakes.