While one person hesitates because he feels inferior, the other is busy making mistakes and becoming superior.

If you wish to make a man your enemy, tell him simply, 'You are wrong.' This method works every time.

Psychologically I should say that a person becomes an adult at the point when he produces more than he consumes or earns more than he spends. This may be at the age of eighteen, twenty-five, or thirty-five. Some people remain unproductive and dependent children forever and therefore intellectually and emotionally immature.