To do something useful for people, not to live in vain, to move humanity thought only a bit forwards
Allegedly a quote of K. E. Tsiolkovsky that has been impressing me since years. It sounds exaggerated because common wisdom goes that to move humanity is reserved for a few greatest minds. But that quote has something appealing for everybody, especially nowadays in the time of globalization when concerted action of us, people, has occasionally a huge impact.