Only people are unpredictable. What was the last sentence?

The phrase "The precipice will eventually have a bottom, and only the human heart is unpredictable" means that even if the abyss is deep, it will have a bottom, but the human heart is unpredictable. It means that no matter how deep the abyss is, there will be a bottom, but people's hearts are sinister and unpredictable. No one believes when the heart is revealed. Even if the deception is poor, some people are willing to fall for it. Full text: The abyss will eventually have a bottom, but the human heart cannot be measured. No one has ever asked the truth, but the routine is popular. This is a limerick written by modern people, regardless of its origin. This is a folk saying. Literally, it can be understood as: do good things without bad thoughts of hurting others, but also beware of others. Source: "Caigen Tan": "The heart that harms people is indispensable, and the heart that prevents people is indispensable. This maxim has also been ignored: it is better to be cheated than to be bullied. This kind of vigilance is also vigilance, two languages coexist, smart and honest.