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Everyone has willpower. It is inherent to the makeup of the physical-astral-mental-emotional body. The center of willpower is the manipura chakra, located at the solar plexus. Unlike other energies, the more willpower we use, the more willpower we have to use. This happens when we work a little harder than we think we can, do a little more than we think we can do. By putting forth that extra effort, we build up a great willpower that we will always have with us, even in our next life, the next and the next.
— Satguru Sivaya Subramuniyaswami (1927-2001), founder of Hinduism Today