Any person who understands the Zero can cultivate and realize the fruition.
All dharmas arise from causes and conditions, and also cease because of causes and conditions. This is the principle of rebirth, and it is also the principle that "When something reaches an extreme, it will turn around. When misfortune reaches an extreme, prosperity comes." This is also true of all dual dharmas in the world.
"Dual dharmas": when good reaches an extreme, it becomes bad. When something becomes bad to the extreme, it becomes good. For instance, at birth we are good, but by the time of death, we are bad. Coming into being, dwelling change, and extinction: after something comes into being, it dwells, then undergoes change, and finally ceases to be. Birth, aging, sickness, and death follow the same principle. After we are born, we gradually grow old, and in old age we contract sicknesses. Sickness then brings about death. These are all conditions. Everyone undergoes birth and is glad to be born; everyone must die, but everyone fears death. If you are neither glad to be born nor afraid to die, you have Samadhi power. Why do people fear ghosts? It is because ghosts are grotesque and frightening, menacing and capable of killing people. Fear of ghosts is a form of the fear of death. If you didn't fear death, you wouldn't fear anything. You wouldn't be afraid of ghosts, spirits, goblins, demons, monsters, or anything at all. If you are afraid of something, you cannot be proper. You can attain proper Samadhi and reception only if you have no fear. A person who possesses Samadhi power has the attitude:
The meaning is, if someone were to slice my head off with a knife, I wouldn't mind too much. I wouldn't be moved. Why not? Because I've already put an end to birth and death - "Everything is done, and there is no more rebirth." When you attain the One, all things are done.
However, attaining the One is not enough. You must find a way to get back to the origin and turn it into a Zero. The Zero is an ineffably wonderful principle. Any person who understands the Zero can cultivate and realize the fruition. How can you understand the Zero? You must first understand the One. "When you attain the One, all things are done." It is beyond the marks of speech, words, and conditions of the mind. Sweep away all dharmas, and separate from all marks. "Not a single dharma exists; all dharmas are empty." If you want to attain this kind of state and realize this principle, you must first attain the One. You shouldn't think the One is so simple.
Why is heaven able to shelter the myriad creatures and things? Because it has attained the One. Why is earth able to nurture the myriad things? Because it has attained the One. If the earth lost the One, there would be landslides, earthquakes, tidal waves, and all kinds of disasters. Wherever the One is lost, there will be incessant calamities. If the One is not lost, the earth will be peaceful and secure.
When a person attains the One, he becomes a sage. If a person really attains the One, he will escape rebirth, realize sagehood, and open up his wisdom. When people have lost the One, they undergo rebirth in the six paths, and suffer all kinds of afflictions and ignorance. The eighty-four thousand afflictions all come about because you have lost the One. If you attain the One, then afflictions will turn into Bodhi and birth and death will become Nirvana, it's as easy as turning over your hand, not difficult at all. So why haven't you been able turn afflictions into Bodhi, and birth and death into Nirvana? It's because you've lost the One, and you've gone to two, three, .., ten. From ten you go to limitless powers of ten, and hundreds of thousands of afflictions come up. Thus the One is very important. But once you lost the One, it's not easy to regain it. And going from the One back to the origin, to Zero, is even more difficult.
Here's another simple analogy. When is it called the One? When is it called the Zero? During the period from ages one to fourteen for girls and ages one to sixteen for boys, the One is not yet lost. When is it the Zero? From the time of conception until birth is the stage of the Zero, because there are no random thoughts, afflictions, greed, anger, or stupidity. But once you learn to eat, greed for food arises when you're hungry; and then greed, anger, and stupidity all start to occur. But at this point you still haven't lost the One. This is the start of your life as a person, and the Zero has become the One. The One is still very complete, and it is the beginning of everything. When you experience the changes of people and things, more things are added on top of the One, so it becomes two; two becomes three; three becomes four, ..and it keeps increasing. The more it increases, the heavier the burden gets, and the stupider you become.
The nature is the Zero, and the Zero is the nature. The Zero and the nature have nothing to them at all:
We want to cultivate until we become as simple-minded as a newborn baby. Our mind should be empty, like a child's. We should return to youth in our old age. However, that doesn't mean you should start drinking mother's milk again. Rather, it means you should cast out all thoughts of greed, anger, stupidity, pride, and doubt. That's called "going back to the root and returning to the source." Your thoughts and outlook are like a child's: innocent and pure, without the slightest bit of laziness, greed for advantages, or criticism of other's faults. At that point, "Originally there's not a single thing; where can the dust alight?"
If we can understand this principle and cultivate, then we can truly become enlightened. Why do we listen to lectures on the sutras? Because we want to return to the origin. Why do we cultivate? Because we want to get back to the source, and clean up all the miscellaneous garbage, so that we don't spend all our time on the question of self and others. When someone talks badly of us, we get upset and cannot bear it. If someone were to touch even one hair on our bodies, the pain would sear our hearts. And even if we could benefit the world by pulling out one hair, we wouldn't do it. With such selfishness, we won't be able to cultivate.
A cultivator should not have the mark of self, the mark of others, the mark of living beings, or the mark of a life span. Not having the mark of self doesn't mean that when it's time to work, you make everyone else work. Not having the mark of others doesn't mean when it's time to eat, you say, "I have no mark of others, so it's no problem if I eat more." You may not have the mark of others, but other people do have the mark of others. Or perhaps when you are fighting, you claim to have no mark of living beings, or when you eat meat, you say you have no mark of a life span. That's wrong. Those are all improper ways of thinking. What's the right way?
So in cultivation, we should never seek anything for ourselves or scheme for our own benefit. We should always try to think on behalf of others.