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When you know principles that can motivate you, you will then know principles that can motivate others. Conversely, when you know principles that can motivate others, you will then know principles that can motivate you.

Napoleon Hill, W. Clement Stone (1991). “Success Through a Positive Mental Attitude”, p.119, Simon and Schuster
When you know principles that can motivate you, you will then know principles that can motivate others. Conversely, when you know principles that can motivate others, you will then know principles that can motivate you.