What do you mean by "moving four bodies"?

Confucius' The Doctrine of the Mean: "When you see a turtle, you move four bodies." In other words, we can see the signs of ups and downs through the prediction and behavior of turtles.

The four bodies here are not only two hands and two feet, but also body, phase, sound, shape and so on, which can be used to predict and judge, but what is the basis of judgment and prediction? Then you need sincerity! If you are all in a daze and confused, is there any fun in observing things outside? A person who can look at the world with his motherland in mind must first put aside everything else and focus on the affairs of all countries in the world.