At IMD we had an HR professor ...

At IMD we had an HR professor who was a psychologist as well. He had a chart showing results of numerous studies of people at different ages and asking if they were content or happy. Funny thing about mathematical curves they tend to trend, ie if you start on a path of contentment, it is rare the the curve inverts or a step change makes you all of a sudden unhappy. Some people have a lot of burdens to bear in this life, but we adopt very quickly to our new circumstances. And those who are already on a strong "happy trajectory" seem to somehow, pick themselves up, and stay on track. So if I win the lottery today, in a few months it is normal that I have so much more money, but now this is the norm, and I have new expectations and goals, by the way higher ones. The hardest thing that we have to face is to change a tragectory, so if I am unhappy my whole life, it seems it is almost impossible to become happy or fullfilled as an old person. Like many things, youth is more flexible and have the time to change tragectory. What about us poor old folk? or the young person who starts off in the wrong direction. Which is more difficult to change?