Dr. Taimni was a Physics and Chemistry professor at Allahabad University, as well as an accomplished yogi.
According to Taimni, hath yogic prāṇāyām involves manipulation of pranic currents through breath regulation for bringing about the control of chitt-vritti and changes in consciousness, whereas rāj yog prāṇāyām involves the control of chitt-vritti by consciousness directly through the will of the mind.