God gave us the tools and we mustn't squander them. That's why wisdom is an obligation. Wisdom is the water that helps us grow. Without it, we get stuck. Happiness is also an obligation.
Western society thinks that happiness is optional.
But really, being happy is part of being considerate to those around us. When a person lives optimistically and joyfully, his energy spreads. A miserable person, likewise, spreads misery. Imagine how you would feel if your parents or your friends were always unhappy. So work on giving the same happiness to others that you'd want them to give you.