P.D. Ouspensky
Author: P.D. Ouspensky
Publisher: Vintage (1971)

Q. What is the relation between si 12, mi 12 and sol 12? A. You will understand this later. If you like, I can say that mi 12 refers to the emotional centre, sol 12 to the instinctive centre and si 12 to the sex centre. We can work only on mi 12. We have too little of si 12, and sol 12 passes higher to a very small amount of H 6 which, though it is so small, keeps the higher centres alive.