The light that burns twice as bright burns half as long.
Edited to add a favorite Hitchens quote, from Letters to A Young Contrarian:
Beware the irrational, however seductive. Shun the ‘transcendent’ and all who invite you to subordinate or annihilate yourself. Distrust compassion; prefer dignity for yourself and others. Don’t be afraid to be thought arrogant or selfish. Picture all experts as if they were mammals. Never be a spectator of unfairness or stupidity. Seek out argument and disputation for their own sake; the grave will supply plenty of time for silence. Suspect your own motives, and all excuses. Do not live for others any more than you would expect others to live for you.