Sri Aurobindo translates Prashna Upanishad, Sixth Question, Verses 1-2: “Then Sukesha the Bharadwaja asked him: ‘Lord, Hiranyanabha of Koshala, the king’s son, came to me and put me this question, ‘O Bharadwaja, knowest thou the Being and the sixteen parts of Him?’ and I answered the boy, ‘I know Him not: for if I knew Him, surely I should tell thee of Him: but I cannot tell thee a lie: for from the roots he shall wither who speaketh falsehood.’ But he mounted his chariot in silence and departed from me. Of Him I ask thee, who is the Being?’ To him answered the Rishi Pippalada: ‘O fair son, even here is that Being, in the inner body of every creature, for in Him are the sixteen members born.’ ”
The first thing we notice in the introduction to the sixth question is the humility and adherence to truth exemplified by Sukesha when he was asked a question of considerable depth. He did not try to explain, pontificate or describe, but politely noted that he was not in a position to provide an answer as he did not know how to answer. This shows a willingness to learn and grow on the part of the student, as he recognizes that he does not have the complete knowledge.
The question related to the Being of 16 parts. The term translated here as “Being” is Purusha. Sri Aurobindo elsewhere describes the Purusha as the aspect of conscious existence in the creation, in the aspect called the Kshara Purusha. There is also the unmanifest aspect which is called Akshara Purusha, and as the Bhagavad Gita notes, there is a supreme Purusha, the Purushottama, which encompasses and exceeds both the Kshara and Akshara aspects. In this case, the question revolves around the Purusha with 16 parts, which implies it is the aspect manifest in the creation. The response by the Rishi to the disciple’s question indicates that this Purusha is housed within the body of every creature. This does not imply that it is contained within the body exclusively; rather, it creates a link between the consciousness out of which, and by which, the creation manifests, at the transcendent and universal levels, and the individual forms and beings so created.
The question raised here is really about the consciousness that constitutes the awakened beings in the world. Whence does it arise and what is the relation between the activity of that consciousness in the individual and the life and existence of that individual. What is, therefore, the essence that provides life to creatures, and which, upon departing, takes the life away.
The 16 parts are the five great elements, ether, air, fire, water and earth, along with the five senses of perception, the five senses of action and the mind. They are the creation of Prakriti, the active element of Nature put into action by the Purusha.
Sri Aurobindo, The Upanishads, Prashna Upanishad, pp.297-315