i z m

-To pass SEAL training, there are series of long swims that must be completed. One is the night swim. Before the swim, the instructors joyfully brief the students on all species of sharks that inhabit the waters off San Clemente. They assure you however, that no student has ever been eaten by a shark, at least not that they can remember. But you are also thought that if a shark begins to circle your position, stand your ground. Do not swim away. Do not act afraid. And if the shark, hungry for a midnight snack darts towards you, then summons up your strengh and punch him in the snout, and he will turn and swim away. 

There are a lot of sharks in the world. If you hope to complete the swim, you will have to deal with them. So if you want to change the world, don't back down from the sharks.

William H. McRaven, United States Navy Admiral.