Prana is Vital or Sentient Energy and Yama is Control or Expansion. Hence, Pranayama is the controlled expansion of the life force. The Universe is Prana. Life is Prana. Consciousness is Prana. This is the View that must be held on to while undertaking the bliss-inducing Pranayama techniques.
The objective of Pranayama and the various Pranayama Techniques is to achieve
Sensitization or Familiarization
Harmonization
Amplification
Unified Concentration
as concerns Prana.
So, the practices are also four-fold, with the initial practices being aimed at the cognition of internal and subtle internal processes. Cognition can be achieved best and quickest, with the aid of visualization. Therefore visualization of a physical nature becomes the first part of the Sensitization practices.
Harmonization occurs when the cognized prana is seen in its various sub-divisions along with their psycho-motor functionality. Just by seeing these internally, balance is brought about in them, through the process of Prana-channel purification. The pranayama techniques practiced for harmonization are Chandra and Surya Bhedana.
Thirdly, once Harmony has been achieved and the individual is prepared to evolve willfully, the practices of vitalization begin, where Prana is taken in from the ambient Universe all around and acting like a battery, we start to build up Prana power, this being the stage of Amplification. Kapalabhati and Bhastrika are the Pranayama Techniques used for Amlification of Prana.
Lastly comes the stage of Kevala Kumbhaka or non-breathing where due to the Pranic power of Unified Concentrated Prana, the body ceases all breathing automatically, being in a state of physical stasis but with the consciousness projected into higher planes of Being. The Unified Prana Power flows into the only Nadi that can take their unified power, that Nadi being termed the Sushumna.
Since Prana and mind are reflections of each other in the body, regular practice of Pranayama leads to control over Prana, which is also control over the mind. The mind being much harder to control than the breath, and the Prana Power being directly co-related to the breathing process, the Pranayama techniques form the bedrock for the higher mind-control and expansion practices that follow.
