Prajapati teaches Indra about what the Atma is, by telling him what it is not.
Explaining the phenomenon of the Atma is one of the important functions of the Upanishads. Atma is derived from ‘at’, which means to pervade. Hence the Atma is all pervasive. Many Upanishads elaborate on the nature of the Atma. The arguments are very similar though not exactly the same. Here the discussion put forth in the Chandogya Upanishad (VIII-vii to VIII-xv), which is a part of the Sama Veda, is described. This discussion also illustrates the question answer structure of the reasoning process that is often found in the Upanishads.
Prajapati proclaims that the Atma is free from evil, free from old age, free from death, free from sorrow and free from hunger and thirst. He who discovers and understands that Atma attains all the worlds and all the desires. Hearing this the demi-God Indra and the Demon Virochana approached Prajapati so that they may learn the secret of the Atma. The two served Prajapati for thirty-two years at the end of which Prajapati asked them the reason for their coming. When he was told the objective of their mission he said that the body that is seen as a reflection is the Atman. Indra and Virochana then left for their abodes and Virochana began to teach this to the Demons.
But Indra was not convinced. When the body gets blind the reflection gets blind and when the body ages the reflection, therefore the reflection cannot be the Atma. He returned to Prajapati and voiced his doubt. He then served Prajapati for another thirty-two years. After that Prajapati told Indra that the person one sees in one’s dreams is the Atma. This person does not get blind when the body gets blind nor does this person age when the body ages. His doubts cleared Indra left Prajapati.
But soon fresh doubts began to engulf Indra. The person in one’s dreams is conscious of pain and therefore cannot be the Atma. He returned to Prajapati and served him for another thirty-two years. Then Prajapati told Indra that the person in a dreamless sleep is the Atma because the person in a dreamless sleep feels no pain. With this knowledge Indra left Prajapati.
However he was still not satisfied. The person in a dreamless sleep has no consciousness at all. Such a person is nothing. So how can he be the Atma? Confused, Indra returned to Prajapati. Prajapati asked Indra to serve him for five more years, thus bringing the total of Indra’s servitude to a hundred and one years. He then gave Indra the final lesson.
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