I've been thinking a lot about what it means to be an adult. To me, being an adult means owning up to your responsibilities and making reasonably rational decisions. I say reasonably because there are things that can't/shouldn't be rationalized. For example, love between exact opposites or why they stopped showing Captain Eo at DisneyLand (completely irrational).
On the opposite side of the equation, we have emotion. The western world has a love/hate relationship with emotions. In America, it is written that we should all be working on that constant pursuit for happiness. Some of the best movies are about people who do this.
As an adult, we all have to balance this.