People, there are many things that are not needed by the body for survival, but the desire of the soul. For example, prawns, hairy crabs, sea cucumbers, abalone, shark's fin, birds and animals are not what the human body needs, but the desire of the human soul. Desire is infinite and intangible. Since desire is infinite and intangible, what it needs is infinite and intangible, so the ups and downs of these things are infinite and intangible, and there is no law at all. We can only rely on our own diligence (intellectual diligence, not physical diligence) to keep track of the market, analyze on the spot, and make the closest judgment in time.