The followers of Hinduism were the first people to come up with the concept of Advaita, which puts forth the concept that all beings in the world are equal. Here are a few points from the perspective of the soul that proves it.
In Bhagwad Gita, Lord Krishna mentions that the souls use bodies just like dresses to enjoy life and they leave their dresses in the form of death to assume a new dress (life). How true could this be? Here are a few thoughts from scientific knowledge that may prove this right.