The five un-quintuplicate rudimentary elements and their effect, the subtle body, both together constitute what is called the HIRANYAGARBHA. The material subtle body has seventeen parts, viz. the five vital forces, the ten organs of perception and action, the mind and the intellect. This is said to be the subtle body of the Atman (Soul). When the sense-organs are quiescent or withdrawn, the knowledge arising out of impressions of the waking state and the imaginary objects there perceived, are together called the dream state. The TAIJASA is the Atman which identifies Itself with both the dream state and the subtle body. These three, i.e. the subtle body, the dream state and the TAIJASA are represented by the second letter U in AUM.