"Perhaps our most important quality as humans is our capability to self-regulate. It has provided us with an adaptive edge that enabled our ancestors to survive and even flourish when changing conditions led other species to extinction. Our regulatory skill or lack thereof is the source of our perception of personal agency that lies at the core of our sense of self."
-- Barry Zimmerman
Zimmerman, B. J. (2000). Attaining self-regulation: A social cognitive perspective. In Handbook of self-regulation (pp. 13-39). Academic press.