In the mind’s arena, willpower (a facet of “ego”) represents a wrestling match between top and bottom systems. Willpower keeps us focused on our goals despite the tug of our impulses, passions, habits, and cravings. This cognitive control represents a “cool” mental system that makes an effort to pursue our goals in the face of our “hot” emotional reactions—quick, impulsive, and automatic.
From "Focus: The Hidden Driver of Excellence", by Daniel Goleman
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