Here's an interesting interview. One caveat: he's not talking about happy as in, "joy" or "fun". He's using it to mean "open to positive possibilities". I wish those who studied this field would use a word other than "happy", which generates skepticisim. I took the Positive Psychology course with Tal Ben-Shahar and would recommend it to anyone interested in learning how to develop their own and others' abilities to open the mind, develop new neural pathways, and develop more positive relationships.