everything within this universe has two sides, just like the two sides of a coin.  we have light and we'll have darkness; we have good things and we'll have bad things; we have happiness and sure we'll have sadness; there's love and there's hatred! how much joy you gain from one person, you can have equal amount of sorrow from the same person.  it seems that the most secure thing to find out the balance point. but, where's the equilibrium? even if you found out that, the question is: will you be perfectly happy to stay at that point forever?