Sally Kohn: One childhood memory I have of like really having fun is being on a cruise ship. What I find fun can be totally different from what you find fun, but still there has to be some phenomenology and we're not quite sure how to just put our finger on it. She says the psychologist who coined this term flow said that flow is quote, the kind of feeling after which one nostalgically says that was fun or that was enjoyable. So these are all things where they seem to be interconnected, she says.