You exist without the feeling of existence.
When you see a mistake in somebody else, try to find if you are making the same mistake.
If everyone practiced yoga, pharmacies would have to close.
In your discipline, if doubt comes, let it come. You do your work and let doubt carry on with its work. And let us see which gives up first!
Yoga uses the body to discipline the mind and to reach the soul.
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.