The document discusses research into what makes people happy. It notes that factors like wealth, social class, intelligence and race are poor indicators of happiness, though poverty is linked to unhappiness. Most people report being moderately happy, around a 6 or 7 out of 10, regardless of their circumstances. Marriage is associated with greater happiness than being single. However, having children tends to reduce reported happiness levels, especially during the teenage years, though happiness returns once children leave home. The document speculates that people may value having children more than pure happiness or stay in bad marriages for the sake of their children.