You were born with the greatest weapon in all of nature — the rational, conscious mind. 

Robert Greene

To think is easy. To act is difficult. To act as one thinks is the most difficult of all. Johann Wolfgang von Goethe

Right thinking comes with self-knowledge. Without understanding yourself, you have no basis for thought. Jiddu Krishnamurti

The will to win, the desire to succeed, the urge to reach your full potential... these are the keys that will unlock the door to personal excellence.