Is not a kiss the very autograph of love?
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 a the age of eighteen, twenty-five, or thirty-five. Some people remain unproductive and dependent children forever and therefore intellectually and emotionally immature.
While one person hesitates because he feels inferior, another 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.