On the relationship side, if you teach people to respond actively and constructively when someone they care about has a victory, it increases love and friendship and decreases the probability of depression.

When well-being comes from engaging our strengths and virtues, our lives are imbued with authenticity.

Once a depressed person becomes active and hopeful, self-esteem always improves. Bolstering self-esteem without changing hopelessness, without changing passivity, accomplishes nothing.

Not only do happy people endure pain better and take more health and safety precautions when threatened, but positive emotions undo negative emotions.

Optimism is invaluable for the meaningful life. With a firm belief in a positive future, you can throw yourself into the service of that which is larger than you are.

Ten years ago, when I was on an airplane and I introduced myself to my seatmate, and told them [I was a psychologist], they'd move away from me. ... And now when I tell people what I do, they move toward me.

Psychology is much bigger than just medicine, or fixing unhealthy things. Its about education, work, marriage - its even about sports. What I want to do is see psychologists working to help people build strengths in all these domains.