I don't think being 'happy' means having a smile on your face all the time. Just some of the time. It also involves lots of other emotions and feelings, including those that you can only get from doing a worthwhile job, hopefully part time! I agree with the sentiments above about people who get addicted to chasing money........'and then you find that, ten years have got behind you, no one told you when to run, you missed the starting gun.....and you run and you run to catch up with the sun but its sinking, shorter of breath and one day closer to death'