Socrates once asked the simple question - "Who am I?" For thousands of years, philosophers, theologians, scientists and psychologists have contemplated the answer to this question. In a modern world filled with distractions, an individual is more prone to disillusionment. Self-knowledge, the foundation for physical, spiritual, and mental growth, nurtures confidence and builds a defense system against despair. Awareness and knowledge of the self is crucial to proper overall development. The author examines definitions of the self given by physicalists, scientific realists and the cognitive method of Bernard Lonergan, S.J. who defines the self as a rational and spiritual being. Examples of near-death experiences and temporal lobe epilepsy will be used to help explain the different theories. The author thoroughly discusses the importance of self-knowledge in every dimension of human growth and encourages the reader to reclaim the desire to know the self.