Traditional psychology typically relies on averages to evaluate people's level of happiness and fulfillment. If someone's level is below the average, traditional psychology aims to bring them back to the "average index." Also, traditional psychology isn't focused on things that bring people above average but on what makes them go down.

Yet, this methodology has a significant disadvantage. Fixation on averages makes it impossible to reach perfection. Imagine the situation: There are ten Harvard students. Eight have depression because of the stress that studying gives them. Considering this information, traditional psychology would take those eight students and their level of happiness as an average index. This seems reasonable since they represent a major part. But, going this way, traditional psychology ignores an anomaly: two students with no depression at all! It's significant because those two students, who aren't prone to depression, have a much greater chance of success in their studies and future careers.

The realization that we need to focus on positive aspects led to the emergence of positive psychology. Its objective is to identify factors that contribute to people's success and use this knowledge to enhance the average level of success. This raises the question: what makes those two students excel where the other eight suffer setbacks?

The author spent twelve years being among students at Harvard and traveling around the globe to find out what exactly brings people above the average. As a result, he concluded that a person's success highly depends on how they perceive reality. Shawn gives the example of students from Soweto, South Africa. The majority of them interpret studying as both a privilege and a challenge, which is pretty far from Harvard students' perception.