The physical body, the astral body, Prana, intellect or Buddhi, the instinctive mind, the spiritual mind and the spirit are the seven principles of man. Buddhi is pure reason. The seat of Buddhi is just below the crown of the head in the Pineal Gland of the brain. Buddhi is manifested only in those persons who have developed right intuitive discrimination or Viveka. The ordinary reason of the worldly people is termed practical reason, which is dense and has limitations. Prana is the vital force, life-energy or Jiva Sakti. It is the eternal symbol of God. It is the link Hiranyagarbha or Golden son of God. It is the link between the astral and physical body. Prana is divided into physical Prana and psychic Prana. Breathing is external manifestation of physical Prana. All thoughts are due to the vibration of psychic Prana in the Chitta. The causal body or Karana Sarira is the support for the astral and physical bodies. Will is Para Sakti. Get this Sakti—you will get Sat or Existence. Chitta is the sub-conscious mind. It has two layers. One layer for emotion and the other for passive memory. The instinctive mind is the lower nature of human beings. It is the desire-mind or Kama Manas. The spiritual mind is the higher Manas. The seat of the mind is the heart. The mind connected to the Somachakra of the lowermost portion or under-surface of the brain is termed the organ of understanding. By Manonasa or annihilation of the mind is meant the destruction or dissolution of the lower nature, desire-mind. Sankhya Buddhi or Buddhi in the light of Sankhya philosophy is will and intellect combined. Mind is microcosm. Mind is Maya. Mind occupies an intermediate state between Prakriti and Purusha, matter and Spirit.