There is an Arabic saying, "If you wish to know God, you must know yourself." How little man knows while he is in the intoxication of individualism! He thinks, "I am a separate being; you are another; there is no connection between you and me, and we all have our own joys and free will." Did man but know it, his life is dependent not only on the objects and things that keep the body alive, but also on the activity of a thousand minds in a day. Every time a man laughs it is the reflection of his mind, controlled by the power of another person's mind. Why does he feel sometimes sad, sometimes glad, sometimes cheerful, sometimes enthusiastic, sometimes tired without reason, sometimes depressed and exhausted? We meet so many minds throughout the day and night which are reflected in our own mind; and so the thoughts are changed, seemingly without reason, yet the whole activity of life depends on these thoughts and is changed according to them.