How did life become a collection of short unanswered riddles?
First of all, life is not, as you suggest, a collection of short unanswered riddles. There is much more to life than this sort of trivia. Life is, in fact, one of the great forces of nature which have shaped and modified our planet over the millennia. Secondly, your comment has little or nothing to do with your original question and is in fact a completely different question, the answer to which is probably that happiness is usually taken to be a temporary emotion, whereas contentment is perhaps a more permanent state.
