“Even when some things are good, we cannot prompt ourselves to do them even by will. Some people try forcibly to restrain themselves from doing certain things. This will never work because the activity of forcing, constraining, and struggling tends to become a distraction. We become so involved in the negative action that we never progress … Someone might smoke sixty cigarettes a day, and he might understand intellectually that he should not smoke, but he cannot stop. Nobody smokes because they like the idea of inhaling tar and nicotine. There is some other reason … something must happen to such a person that will tell him, “Look here, I can do without cigarettes.” Ideally when we move into the practice of yoga, we begin to develop a process that stops the detrimental. This stopping is not caused directly — we don’t stop the bad, it stops.”
TKV Desikachar – Religiousness in Yoga