There is a verse from the ancients: Two causes in the past, five effects in the present, three causes in the present, and two effects in the future. It briefly explained the twofold cause and effect of the twelve causes and conditions in three lives. The Buddha told the Pratyekabuddhas that these twelve causes and conditions are to reveal the law of cause and effect reincarnation cycle in the past, present and future three lives.
Generally speaking, ignorance is the condition of action, action is the condition of consciousness, consciousness is the condition of name and form, name and form are the condition of the six senses, and the six senses are the contact. There are four verses from the ancients: "Ignorant love takes three troubles, and there are two branches of action as the path of karma, from consciousness to feeling and old age and death. These seven things are the path of suffering." ' This is the principle that the twelve causes and conditions flow through the three paths of confusion, karma, and suffering.
The twelve causes and conditions are another chain of hooks and interlocking relationships. There are also circulation gates and annihilation gates. What is discussed above is the twelve causes and conditions of the flow door. Paccekabuddha is called Ligen among Hinayana saints. They heard the Buddha's talk about the mutual relationship between the twelve branches of cause and condition, and the principle of mutual cause and effect. They realized that the branch of ignorance is the total source of suffering among the twelve branches of cause and condition. Once ignorance is eliminated, all the other eleven causes and conditions will be eliminated. Therefore Pratyekabuddha made up his mind to cut off ignorance. It's like cutting down a tree. Cut the roots first. Once the roots are broken, the whole tree will naturally fall down. Only when ignorance is eliminated can the true nature be restored and troubles eliminated, so it is called the door of annihilation. This is the principle of the twelve causes and conditions practiced by the sages of Pratyekabuddha