You can see the truth in a small place. From the microscopic world, we can see the mystery of the macroscopic world; And vice versa, that is, we can also see the big and small, from macro to micro. Buddhism believes that a grain of sand can see three thousand worlds, which is now scientifically called cosmic holography; The universe is contained among leaves, and there is a hole in the petals. As the saying goes, a flower is the world and a leaf is the Buddha.