My empirical study of happy people comes down to these three points: * Have low expectations * Enjoy simple things * Don't care too much
You have to take into account the difference of each mind's disposition between people. There are people who would just read those 3 bullet points and be disgusted. Some people need an empty pointless life and are "happy". Some people need struggle, challenge and difficulty, otherwise they cant be happy.
People and minds are extremely complicated. To me, having low expectations and not caring too much is a sign of a defeated person with no spirit. That is sad