If you can motivate yourself, 

you don't have to depend on any external method.

Great men hallow a whole people, 
and lift up all who live in their time.

People who are unable to motivate themselves must be content with mediocrity, no matter how impressive their other talents.

 Motivation is a fire from within.  

If someone else tries to light that fire under you,

 chances are it will burn very briefly.