Summary of Shankara's System

The fundamental principle of Shankara’s teaching is that the pure, innermost ‘Self’ is the ultimate reality. This Self (which must not be confused with the ‘ego’) is a spiritual kernel of the same kind as Brahman or Godhead, the ultimate reality.

When a man overcomes ignorance or ‘avidya’ (the word has a very wide connotation which will be explained later) and grasps intuitively that the Universe is merely an external phenomenon, and realises the identity between the Self and Brahman he becomes a ‘liberated’ soul waiting only for his final liberation from the body by death.

The Self or Brahman cannot be described because it has no ‘qualities’ in the ordinary sense though it is sometimes said to be of the nature of pure being pure consciousness and pure bliss.

The material universe of forms and things is grounded in Brahman, but its formation therefrom cannot be described or formulated.

It functions on the basis of the law of ‘karma’ that is of cause and effect; but its ultimate cause is Brahman which has created the material world and started the process of change that we see occurring in that world, all creation is, however, ‘Maya’ or the power of illusion. 

Within the realm of maya the universe exists and can be conceived as a creation of Brahman, who can also be conceived as a personal God; though from the standpoint of ultimate reality even a personal deity is a product of maya.

The causal law itself is ultimately unintelligible, because it is an illusory concept of name and form. There is no more essential difference between effect and cause than between a moulded pot and the clay from which it is made.

The world as caused by Brahman is an illusory superimposition (adhyasa) of phenomenon on the basic reality—like a rope which is mistaken for a snake or the mirage-lake seen on the desert sand.

It follows logically therefore that Shankara should urge the renunciation of transitory things and the acquisition of ‘right knowledge’ as the only means of attaining ‘liberation’.

~Y. Keshava Menon, "The Mind of Shakaracharya"