The big insight Csikszentmihalyi and Bennet figured out in 1975 with their study of flow wasn’t necessarily the description of any one individual’s experience as much as it was in the sheer number of data points. With over 175 interviews, patterns started to emerge. With so many reference points, they were able to cross reference the descriptions of activities as diverse as sitting and  looking at pieces on a board to hanging from a rock trying to avoid bodily pain and propelling yourself up a mountain. This study paved the way for later studies that involved thousands of people with thousands of data points to gain objective insights from such tricky subjective experiences such as happiness.