This book serves as an introduction to the six systems of Hindu philosophy. Though these six systems are different in their approaches to the truth, they are unanimous as far as the final goal of humankind is concerned, which is, total eradication of suffering and attainment of state of eternal peace.
The Atman alone is eternal. Hospitals will tumble down. Railroad givers will all die. This earth will be blown to pieces, suns wiped out. The Atman endures for ever.
-Swami Vivekananda