The philosophy of Advaita,is intended to be practical so that it becomes possible to play one’s part in the world in a better way and with greater efficiency and effectiveness than would otherwise be the case.
Advaita is a Sanskrit word, which literally means ‘not two’.
The word ‘dvaita’ means ‘two’ and the prefix ‘a’ gives the meaning ‘not two’ or ‘non-dual’. The main proponent of this philosophy was Shankara, who is thought to have lived in the eighth century in India.
According to this philosophy what is present is true existence, which is both transient and unchanging.
An analogy is given by way of illustration. Gold is a single substance. Out of this single substance of gold, rings, ornaments, and innumerable other forms may be fashioned. When we see a ring we call it a ring, but it is still the same gold. If that gold is melted down and fashioned into an ornament, we would call it an ornament, but it is still gold. It never loses its essence of gold. Only the form changes, not the essence. In this analogy the rings, ornaments etc. represent all the things of the world that we see, hear, touch and so on. All of these forms are transient. Even something as mighty as a mountain will not last forever. The substance of gold represents that which does not change. It is the underlying existence or essence.