The Buddha said in the Diamond Sutra: Everything is illusory. It's just that many people don't understand it deeply. The "monsters, ghosts and bodhisattvas" seen in practice are all illusions, that is, "demons". Buddhism also says: those who are possessed by demons suffer from demons. A troubled devil can drag out an ignoble existence in a good way, so he is called a thief of the devil. Inner demons refer to all "demons" that disturb the body and mind and hinder practitioners. In fact, if no one has the guidance of a "straight-looking" teacher in the process of practicing Buddhist meditation, it will easily lead to insanity and obsession. If you don't know the "magic" correctly, it will cause endless harm to the yogi. It violates the teachings of the Buddha, science and people's physical and mental health. Because it is difficult to make it clear at once, I will only share my understanding of a Buddhist scripture today. Buddha said: those who observe illusions are not illusions (this is the essence of practicing meditation and the method of treating demons). For example, eating sugar feels sweet, knocking on the table feels hard, and seeing roses feels red. Its essence is nothing more than the "mode" of atoms in sugar molecules (carbohydrates) and the "mode" of wood fibers combining with each other, while red is only the result of specific atoms absorbing light of other frequencies and reflecting energy waves of another oscillation frequency. The essence of matter itself has nothing to do with you, but the sweetness you "eat", the hardness you "feel" and the redness you "see. And the "energy" in the "energy" you eat, feel and see is everything (meditation requires a deep understanding of that "energy"). Buddha has made it very clear that the external material world is an illusion created by ourselves in the brain, which is neither true nor true (corresponding to quantum mechanics in physics). When you scientifically understand how the "mind" creates "magic", illusion and dreamland, everything is so simple, so relaxed and so happy! One thought can drive away the "devil". So how does the "heart"-brain-create "demons" and "strange sights"?
There are more nerve connections from the brain to the ear than from the ear to the brain. There are ten times more nerve connections from the brain to the eyes than from the eyes to the brain. Common sense holds that the world we see is generally determined by the stimuli accepted by our senses, which is called "bottom-up". In fact, the world we see through scientists' research is more determined by the "top-down" mechanism. Top-down means that what you perceive is determined by your brain. More precisely, it is the result of the brain issuing instructions to the senses. To a considerable extent, what we see, hear and grasp (such as the cup in our hand) is the result of active plastic surgery and intervention, not the result of passive feeling.
That is, the external world (stimulus) we see is ignored and distorted by the brain. The brain can create its own images, even you can't control them. It's just like looking at two cubes that change automatically-your brain will "force" you to keep seeing different images changing. What we see is an "illusion", one that forms expectations in advance (expecting to see Buddha or fearing to see devil, hell or heaven), and one that transforms the information that enters our eyes into the "real world" that we see.
Dreaming is the most direct, obvious and transcendental "masterpiece" of our brain. For example, if you recall your dreams, you will find that you will feel pain, be surprised, see and hear something. In your dream, you talk to people you know in normal language and tone (you will see strange sights and say strange things). In other words, dreams and reality are essentially the same thing.
When we meditate, meditate, meditate. What is the brain doing? Basically, the brain only receives a few external "stimuli" (limited by the senses), ignores and distorts the received "stimuli" to create a picture and then shows it to itself. This is the origin of the illusion seen in meditation! It's like thinking about what Yin is showing. Don't be fascinated by illusions when practicing! Read more Buddhist scriptures and broaden your wisdom! There is no amitabha in the south!