When you have chosen a great purpose, and are certain you have chosen well and wisely, concentrate upon it. Bend your best energies to it. Guard yourself against subtle and innumerable influences that tend to divert you from it. Make that single great purpose the definite aim of your daily life. Be enthusiastic about it.
Your thought and time will be solicited by many influences, and you will do well to take special means to protect yourself against them. Make your resolutions so clear and firm that nothing can lure you from your chosen path of purpose and duty. Substitute doing for dreaming, and achievement for wishing. The great things of the world are done by people who specialize and concentrate.