In order to make it easier to understand, the ancients used four common things instead of the above four images. These four common ones are "wood fire and gold water". The concrete replacement methods are: wood-shaoyang; Fire-the sun; No gold and yin; Water-moon.
Extended data
These four images have obvious repeatability. The four elephants correspond to the four seasons of the year and have obvious periodic changes. If the seeds of plants and the offspring of animals are regarded as special ways of life regeneration, then these four images correspond to the four stages of life: birth, growth, old age and death, and life is also periodic. The change of four images is the general law of the development and change of things. Generally speaking, this is very special.
Take animals as an example, the four stages of birth, growth, old age and death have not been completed. Some animals don't leave offspring, so there is no rebirth of life. For animal and plant life, contingency exists, but it is undeniable that life changes periodically. The change of other things is the same, and the general law cannot be denied because of special changes.
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