What is fun?

What is the definition of fun? Well, according to Google it is 'enjoyment, amusement and light hearted pleasure' although I'm sure many people believe it's child's play which should die out by the age of 16. My inspiration for this post was a rerun of a British sitcom called Miranda where the main protagonist is trying to impress her boyfriends father by being prim and proper when she gets fed up of this she exclaims (paraphrasing) 'If being an adult means no more fun, then I don't want to be one' this hit me because this has been a large part of my life in these past few weeks, I am at the age where I am expected, not only by adults but also by peers to 'grow up' to act like all other adults that talk about finances like money is something that will go to the grave with them, people who frown upon seeing other adults dress 'provocatively', people who think that smiling at strangers bad. I don't want to be a person that looks down on others and doesn't question and has lost there curiosity, I would rather laugh and be curious, I want to make friends with as many people as possible.
I believe we are taught to act in this prim and proper way, dressing in dark suits, loosing our curiosity, treating people as a stranger on a street, I think we have lost our natural instinct, our natural animal instinct to care about others, skip carelessly, ask questions, wear what ever we want or nothing at all because when we were children this is exactly what we did, we would walk past the homeless man on the street and say to our parents 'why does that man sleep on the street?', we didn't care what others thought and we would go to school dressed as mermaids and run round the beach naked because we didn't care and we would constantly and annoyingly always ask why, so I am asking Why? Why have we become a society that frowns on fun? We were taught to act 'proper' according to others standards.
Getting old is inevitable, growing up is optional!

Holly