We are creatures that are designed for continual challenge. We must grow or we begin to die....So just standing still isn't really an option. We have to move on. If not, disturbances will come.

When the mind is controlled and still what remains is the soul

Backbends are to be felt more than expressed. The other postures can be expressed and then felt. Like in meditation each person has to feel backbends.

A yogi's brain extends from the bottom of the foot to the top of his head

In forward bends, one uses the outer mind while in backbends the outer mind is silenced and the inner mind is made to work.

Is it necessary to practice all these asanas, further and further? Is it necessary to develop scientific researches further and further? To a yogi, the body is a laboratory, a field of experiments and perpetual researches.

The decision to relax rather than to grip, even in the face of impatience or fear, is a conscious and brave choice.