It is only reached by him who says, 'It is! It is!' He perceives it in its essence.

Its essence appears when one perceives it as it is." The old German expression _Istigkeit_, according to Bunsen, corresponds to this.

This also is the name of Jehovah as given to Moses from the burning bush: "And God said unto Moses, I AM THE I AM.

Thus shalt thou say unto the children of Israel, I AM hath sent me unto you." The idea is that God alone really exists, and that the root of all being is in him.

This is expressed in another Upanishad: "HE WHO EXISTS is the root of all creatures; he WHO EXISTS is their foundation, and in him they rest." In the Vedanta philosophy this speculative pantheism is carried further.
Thus speaks Sankara, the chief teacher of the Vedanta philosophy ("Colebrooke's Essays"): "I am the great Brahma, eternal, pure, free, one, constant, happy, existing without end.