I believe that mankind's purpose on Earth is to learn and teach. It's all about education, whether we're learning or teaching music to calculus, or social behaviors to intelligent thought. Learning is the key to success, and teaching comes from that learning.
But me? My purpose on Earth is to serve as a daughter, a sister, and an individual. I have contributed to my mother's happiness, my brother's knowledge, and my own intuition.
All of us were put on Earth to learn and to teach. The teachers teach the unlearned, and the unlearned teach the teachers. It's an equal exchange.