I have always assumed that having a strong sense of self-worth was important. I figured it made a person happier, healthier, more successful, and easier to be around.
In 1942, the mild mannered Clark Kent excused himself from his friend Lois Lane to take an important call. Clark slipped into a phone booth (remember those?), and moments later Superman emerged.
The November/December Scientific American Mind is a tribute to the seven deadly sins. Not that gluttony, envy, greed, sloth, wrath, lust and pride are necessarily laudable traits, but we can learn a lot from them.