In the video: “Les gestes du professeur The Gestures of the Professor” by Fred Forest, Flusser explains that the movement of a hand is characterizing a gesture. That means that the gesture has the structure of his hand. They are mutually dependent. This he calls a manipulation. A gesture is a manipulation. If we want to understand the gesture, we must see the hand structure behind it. And this example also works with all other gestures of the body.
He gives another example by talking and language. Spoken words are the results of the motion of the tongue. Even we are not able to see the tongue, we decoded her as spoken words. The reading of the spoken words is a codified message. Codified a second time through the language English. But if we think of where the words are coming from, we realize that they are coming from the gesture of the tongue. (14:40 – 16:00)