Non-dualism, also known as Advaita in Sanskrit, is a central concept in Advaita Vedanta philosophy. It is the belief that the self (Atman) and ultimate reality (Brahman) are one and the same. This concept is rooted in the Upanishads, ancient Hindu scriptures, and is considered to be the highest truth in Hinduism.

According to Advaita Vedanta, the ultimate reality, Brahman, is the source and essence of everything in the universe. Brahman is described as pure consciousness, beyond all limitations and dualities. It is the ultimate truth and the ultimate goal of human existence.

The self, or Atman, is the individual soul that resides within each living being. It is believed to be a part of Brahman, and therefore, shares the same nature of pure consciousness. However, due to ignorance and illusion, the self identifies with the body, mind, and ego, and perceives itself as separate from Brahman.

The concept of non-dualism in Advaita Vedanta teaches that the perceived duality between the self and Brahman is an illusion. In reality, there is only one ultimate reality, and the self is not separate from it. This is known as the principle of "Advaita" or non-duality.

To understand this concept, the analogy of a wave and the ocean is often used. Just as a wave is a temporary form that arises from and merges back into the ocean, the individual self is a temporary manifestation of Brahman. The wave may perceive itself as separate from the ocean, but in reality, it is made up of the same water and shares the same essence as the ocean.

The goal of Advaita Vedanta is to realize this non-dual nature of the self and Brahman through spiritual practices such as meditation, self-inquiry, and contemplation. This realization leads to the dissolution of the illusion of duality and the experience of oneness with Brahman. This state is known as "moksha" or liberation, and it is considered to be the ultimate goal of human life.

In conclusion, the concept of non-dualism in Advaita Vedanta is a profound and liberating philosophy that teaches the oneness of the self and ultimate reality. It encourages individuals to look beyond the limitations of the material world and realize their true nature as pure consciousness, ultimately leading to the ultimate goal of liberation.