Dazzling light

Learning objectives

To illustrate that light is the intermediary that allows us to see an object. The book receives the light and reflects it. Part of this reflected light reaches our eye when we see it.
To show that an object can only be seen if the light that it sends to our eye is neither too weak nor too strong.

Light has to enter the eye in sufficient amounts in order for us to see. Alhazen, the Persian scientist of the 11th century, was the first to propose this theory. Before him, there were many other theories, including ones that held that something was emitted by the eye to interact with objects being observed.