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!
B.K.S. IyengarYoga, an ancient but perfect science, deals with the evolution of humanity. This evolution includes all aspects of one's being, from bodily health to self realization. Yoga means union - the union of body with consciousness and consciousness with the soul. Yoga cultivates the ways of maintaining a balanced attitude in day to day life and endows skill in the performance of one's actions.
B.K.S. Iyengar