In "The Upside of Your Dark Side, " two pioneering researchers in the field of psychology show that while mindfulness, kindness, and positivity can take us far, they cannot take us all the way. Sometimes, they can even hold us back. Emotions such as anger, anxiety, guilt, and sadness might feel uncomfortable, but it turns out that they are also incredibly useful. For instance:

Anger fuels creativity

Guilt sparks improvement

Self-doubt enhances performance

In the same vein, we can become wiser and more effective when we harness the darker parts of our personality in certain situations. For instance:

Selfishness increases courage

Mindlessness leads to better decisions

The key lies in what the authors call emotional, social, and mental agility, the ability to access our full range of emotions and behavior not just the good ones in order to respond most effectively to whatever situation we might encounter.

Drawing on years of scientific research and a wide array of real-life examples including sports, the military, parenting, education, romance, business, and more, "The Upside of Your Dark Side" is a refreshing reality check that shows us how we can truly maximize our potential. With an appreciation of our entire psychological toolkit, we become whole which allows us to climb the highest peaks and handle the deepest valleys.

Dr. Todd B. Kashdan is a recognized authority on personality, well-being and social relationships. He has published more than 150 scholarly articles and trains professionals to become emotionally and socially agile. He has been honored with the Faculty Member of the Year at George Mason University and the 2013 Distinguished Scientific Early Career Award from the American Psychological Association. His work has been featured in several media outlets, including "The New York Times" and "The Washington Post." He says the things other people want to but are afraid to. Dr. Robert Biswas-Diener has published more than 40 scholarly articles and has trained thousands of professionals on six continents. He is known as the Indiana Jones of Positive Psychology because he has conducted research with groups typically overlooked by psychologists, including Amish farmers, sex workers in Kolkata, Maasai tribes people and seal hunters in a remote corner of Greenland."