Vivarta Vada Or The Theory Of Superimposition

To Sankara the world is only relatively real (Vyavaharika Satta). He advocated Vivarta-Vada or the theory of appearance or superimposition (Adhyasa). Just as snake is superimposed on the rope in twilight, this world and body are superimposed on Brahman or the Supreme Self. If you get knowledge of the rope, the illusion of snake in the rope will vanish. Even so, if you get knowledge of Brahman or the Imperishable, the illusion of body and world will disappear. In Vivarta-Vada, the cause produces the effect without undergoing any change in itself. Snake is only an appearance on the rope. The rope has not transformed itself into a snake, like milk into curd. Brahman is immutable and eternal. Therefore, It cannot change Itself into the world. Brahman becomes the cause of the world through Maya, which is Its inscrutable mysterious power or Sakti.
When you come to know that it is only a rope, your fear disappears. You do not run away from it. Even so, when you realise the eternal immutable Brahman, you are not affected by the phenomena or the names and forms of this world. When Avidya or the veil of ignorance is destroyed through knowledge of the Eternal, when Mithya Jnana or false knowledge is removed by real knowledge of the Imperishable or the living Reality, you shine in your true, pristine, divine splendour and glory.