Add Yahoo as a preferred source to see more of our stories on Google. Tamara, 12, and her grandfather Heinrich Heckeroth are learning how to read and write Sütterlin in a class taught by Birgit Tröße.

Confidence in one's value as a human being is a precious psychological resource and generally a highly positive factor in life; it is correlated with achievement, good relationships, and satisfaction.

♦ UPDATE: Learn about companies that are applying this timeless advice today. A version of this article appeared in the July–August 2008 issue of Harvard Business Review. James L. Heskett is a Baker ...