control the lower vital or a part of the physical vital and then be astonished to find that something intangible but apparently invincible still resists – it is the material vital with so much of the rest as it can influence by its resistance.Sri Aurobindo
Letters of Sri Aurobindo
Volume I - Part 2
Fragment ID: 10147
Yes – they [the lower vital, the physical vital and the material vital] become very clear to the increasing consciousness. And the distinctions are necessary – otherwise one may influence or control the lower vital or a part of the physical vital and then be astonished to find that something intangible but apparently invincible still resists – it is the material vital with so much of the rest as it can influence by its resistance.