The word ‘posture’ is quite misleading because its meaning is widely misunderstood.
Posture actually refers to the way in which a person is stood or moves.
The onus is upon the nature of their action, rather than a shape.

Thought tends to create fixed structures in the mind, which can make dynamic entities seem to be static.

(Will Keepin)

'13 powers', '13 principles', '13 patterns' or '13 ways' would be a more accurate description.

These are the 6 balanced pairs:

1. Hands & feet
2. Elbows & knees
3. Hips & shoulders
4. Back of head & coccyx
5. CV1 & crown
6. Buttocks & armpits

They are sometimes referred to as the '6 harmonies'.