Lecture I

Imagine you run along next to a wagon. If you run just as fast as the wagon, you will not notice the wagon. But when you walk four times slower and yet hold the wagon, then you will notice the pull. The wagon will go on and you will have to hold back if you want to slow it down. And so it is inside the eye. That is the function of the optic nerve which wants to hold back the rhythm which is four times faster. In the arresting is formed what then is perception, which appears as perception of sight, just as you notice the wagon if you run times slower; if you run in the same speed you will not feel it.