A little girl on the beach plays to give herself the power to attract and repel waves. His gestures are synchronized with the movement of a pendulum which itself harmonizes with the sound of the bag and the backwash. The synchronization of the movement of the child, that of nature (the sea) and that of the watchmaking device (the pendulum) clearly demonstrates the causal links that they maintain between them to serve an idea of temporal decomposition. But what exactly are these links? Or, which of these three symbols is the most objective, humanly speaking, of the invention of time? I would lean towards the little girl, who in her all-powerful game, wants to be the organizer of all this imbalance. Beyond Newton's law, gravity or fluid mechanics, it is the course of childhood and its games that makes us aware of the advance of time.