Everyone wants to be happy. If you asked everybody in the world what the purpose of life is, I'm sure the answer 'to be happy' would be near the top of the list. Everyone has different idea of what that looks like, even people in similar situations. If you compared what happiness looks like now to what it looked like a thousand years ago it would be tough to even say the two are the same thing even at the very root.
Think about this for a second. Say you were the only person on earth. You never knew another human, you never even knew that another...